View Filing Data

Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2019	Oct. 28, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	1-14443
Entity Registrant Name	Gartner, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	04-3099750
Entity Address, Address Line One	P.O. Box 10212
Entity Address, Address Line Two	56 Top Gallant Road
Entity Address, Postal Zip Code	06902-7700
Entity Address, City or Town	Stamford,
Entity Address, State or Province	CT
City Area Code	203
Local Phone Number	316-1111
Title of 12(b) Security	Common Stock, $.0005 par value per share
Trading Symbol	IT
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		89,452,966
Entity Central Index Key	0000749251
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 306,727	$ 156,368
Fees receivable, net of allowances of $7,800 and $7,700, respectively	1,028,320	1,255,118
Deferred commissions	197,607	235,016
Prepaid expenses and other current assets	173,851	165,237
Total current assets	1,706,505	1,811,739
Property, equipment and leasehold improvements, net	300,612	267,665
Operating leases - right-of-use assets	652,273
Goodwill	2,939,707	2,923,136
Intangible assets, net	936,313	1,042,565
Other assets	201,934	156,369
Total Assets	6,737,344	6,201,474
Current liabilities:
Accounts payable and accrued liabilities	593,695	710,113
Deferred revenues	1,803,135	1,745,244
Current portion of long-term debt	130,433	165,578
Total current liabilities	2,527,263	2,620,935
Long-term debt, net of deferred financing fees	2,051,507	2,116,109
Operating leases - liabilities	776,562
Other liabilities	462,355	613,673
Total Liabilities	5,817,687	5,350,717
Stockholders’ Equity
Preferred stock, $0.01 par value, 5,000,000 shares authorized; none issued or outstanding	0	0
Common stock, $0.0005 par value, 250,000,000 shares authorized; 163,602,067 shares issued for both periods	82	82
Additional paid-in capital	1,885,370	1,823,710
Accumulated other comprehensive loss, net	(81,264)	(39,867)
Accumulated earnings	1,921,021	1,755,432
Treasury stock, at cost, 74,124,094 and 73,899,977 common shares, respectively	(2,805,552)	(2,688,600)
Total Stockholders’ Equity	919,657	850,757
Total Liabilities and Stockholders’ Equity	$ 6,737,344	$ 6,201,474

Condensed Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 7,800	$ 7,700
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Common stock, shares authorized (in shares)	250,000,000	250,000,000
Common stock, shares issued (in shares)	163,602,067	163,602,067
Treasury stock, common shares (in shares)	74,124,094	73,899,977

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenues	$ 1,000,502	$ 921,674	$ 3,041,828	$ 2,886,575
Costs and expenses:
Cost of services and product development	365,056	336,112	1,099,700	1,060,958
Selling, general and administrative	512,159	447,537	1,545,905	1,396,085
Depreciation	20,704	17,335	60,578	50,456
Amortization of intangibles	31,694	50,852	97,541	152,625
Acquisition and integration charges	1,742	17,114	4,156	96,342
Total costs and expenses	931,355	868,950	2,807,880	2,756,466
Operating income	69,147	52,724	233,948	130,109
Interest expense, net	(24,073)	(26,984)	(73,669)	(99,647)
Gain (loss) from divested operations	0	13,040	(2,075)	38,500
Other income (expense), net	8,024	(827)	6,953	1,193
Income before income taxes	53,098	37,953	165,157	70,155
Provision (benefit) for income taxes	11,710	26,200	(432)	31,719
Net income	$ 41,388	$ 11,753	$ 165,589	$ 38,436
Net income per share:
Basic (in dollars per share)	$ 0.46	$ 0.13	$ 1.84	$ 0.42
Diluted (in dollars per share)	$ 0.46	$ 0.13	$ 1.82	$ 0.42
Weighted average shares outstanding:
Basic (in shares)	89,846	90,854	89,947	90,969
Diluted (in shares)	90,887	92,148	91,089	92,244
Research
Revenues:
Total revenues	$ 840,998	$ 774,188	$ 2,492,427	$ 2,308,426
Conferences
Revenues:
Total revenues	66,286	57,141	259,392	214,481
Consulting
Revenues:
Total revenues	93,218	78,752	290,009	258,106
Other
Revenues:
Total revenues	$ 0	$ 11,593	$ 0	$ 105,562

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 41,388	$ 11,753	$ 165,589	$ 38,436
Other comprehensive (loss) income, net of tax:
Foreign currency translation adjustments	3,553	964	9,078	(38,504)
Interest rate swaps – net change in deferred gain or loss	(11,379)		(50,599)
Interest rate swaps – net change in deferred gain or loss		350		13,557
Pension plans – net change in deferred actuarial loss	41	53	124	164
Other comprehensive (loss) income, net of tax	(7,785)	1,367	(41,397)	(24,783)
Comprehensive income	$ 33,603	$ 13,120	$ 124,192	$ 13,653

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities:
Net income	$ 165,589	$ 38,436
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	158,119	203,081
Stock-based compensation expense	57,893	56,018
Deferred taxes	(50,790)	(4,746)
Loss (gain) from divested operations	2,075	(38,500)
Fair value adjustment - equity security	(9,120)	0
Amortization of lease right-of-use assets	63,692	0
Amortization and write-off of deferred financing fees	4,865	12,205
Changes in assets and liabilities, net of divestitures:
Fees receivable, net	215,132	172,679
Deferred commissions	35,329	38,216
Prepaid expenses and other current assets	(941)	(64,395)
Other assets	(46,954)	23,444
Deferred revenues	70,006	68,895
Accounts payable, accrued, and other liabilities	(182,294)	(79,322)
Cash provided by operating activities	482,601	426,011
Investing activities:
Additions to property, equipment and leasehold improvements	(95,701)	(64,631)
Acquisitions - cash paid	(2,295)	(15,855)
Divestitures - cash received (net of cash transferred)	0	520,709
Cash (used in) provided by investing activities	(97,996)	440,223
Financing activities:
Proceeds from employee stock purchase plan	13,235	11,134
Proceeds from borrowings	5,000	0
Payments on borrowings	(109,612)	(1,120,290)
Purchases of treasury stock	(141,436)	(104,400)
Cash used in financing activities	(232,813)	(1,213,556)
Net increase (decrease) in cash and cash equivalents and restricted cash	151,792	(347,322)
Effects of exchange rates on cash and cash equivalents and restricted cash	(3,728)	(6,444)
Cash and cash equivalents and restricted cash, beginning of period	158,663	567,058
Cash and cash equivalents and restricted cash, end of period	$ 306,727	$ 213,292

Business and Basis of Presentation

9 Months Ended

Sep. 30, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Business and Basis of Presentation

Business. Gartner, Inc. (NYSE: IT) is the world’s leading research and advisory company and a member of the S&P 500. We equip business leaders with indispensable insights, advice and tools to achieve their mission–critical priorities today and build the successful organizations of tomorrow. We believe our unmatched combination of expert-led, practitioner-sourced and data-driven research steers clients toward the right decisions on the issues that matter most. We are a trusted advisor and objective resource for more than 15,000 organizations in more than 100 countries — across all major functions, in every industry and enterprise size.

Segments. Gartner delivers its products and services globally through three business segments: Research, Conferences and Consulting. Our revenues by business segment are discussed below under the heading "Revenue Recognition." During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

Basis of presentation. The accompanying interim condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”), as defined in the Financial Accounting Standards Board ("FASB") Accounting Standards Codification (“ASC”) Topic 270 for interim financial information and with the applicable instructions of the U.S. Securities and Exchange Commission (“SEC”) Rule 10-01 of Regulation S-X on Form 10-Q and should be read in conjunction with the consolidated financial statements and related notes of the Company filed in its Annual Report on Form 10-K for the year ended December 31, 2018.

The fiscal year of Gartner is the twelve-month period from January 1 through December 31. In the opinion of management, all normal recurring accruals and adjustments considered necessary for a fair presentation of financial position, results of operations and cash flows at the dates and for the periods presented herein have been included. The results of operations for the three and nine months ended September 30, 2019 may not be indicative of the results of operations for the remainder of 2019 or beyond. When used in these notes, the terms “Gartner,” the “Company,” “we,” “us,” or “our” refer to Gartner, Inc. and its consolidated subsidiaries.

Principles of consolidation. The accompanying interim condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All significant intercompany transactions and balances have been eliminated.

Use of estimates. The preparation of the accompanying interim condensed consolidated financial statements requires management to make estimates and assumptions about future events. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities, and reported amounts of revenues and expenses. Such estimates include the valuation of fees receivable, goodwill, intangible assets and other long-lived assets, as well as tax accruals and other liabilities. In addition, estimates are used in revenue recognition, income tax expense or benefit, performance-based compensation charges, depreciation and amortization. Management believes its use of estimates in these interim condensed consolidated financial statements to be reasonable.

Management continually evaluates and revises its estimates using historical experience and other factors, including the general economic environment and actions it may take in the future. Management adjusts these estimates when facts and circumstances dictate. However, these estimates may involve significant uncertainties and judgments and cannot be determined with precision. In addition, these estimates are based on management’s best judgment at a point in time. As a result, differences between our estimates and actual results could be material and would be reflected in the Company’s consolidated financial statements in future periods.

Revenue recognition. Revenue is recognized in accordance with the requirements of FASB ASC Topic 606, “Revenue from Contracts with Customers” (“ASC Topic 606”). Revenue is only recognized when all of the required criteria for revenue recognition have been met. The accompanying Condensed Consolidated Statements of Operations present revenue net of any sales or value-added taxes that we collect from customers and remit to government authorities. ASC Topic 270 requires certain disclosures in interim financial statements around the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers, which are provided below.

Disaggregated Revenue — Our disaggregated revenue by reportable segment is presented in the tables below for the periods indicated (in thousands).

By Primary Geographic Market (1), (2)

Three Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Primary Geographic Markets
United States and Canada	$	538,112	$	28,153	$	58,615	$	624,880
Europe, Middle East and Africa	196,121		24,497		26,468		247,086
Other International	106,765		13,636		8,135		128,536
Total revenues	$	840,998	$	66,286	$	93,218	$	1,000,502

Three Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Primary Geographic Markets
United States and Canada	$	502,489	$	22,002	$	45,903	$	8,948	$	579,342
Europe, Middle East and Africa	180,124		25,422		26,255		2,645		234,446
Other International	91,575		9,717		6,594		—		107,886
Total revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674

Nine Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Primary Geographic Markets
United States and Canada	$	1,593,806	$	157,756	$	175,208	$	1,926,770
Europe, Middle East and Africa	583,742		67,520		90,350		741,612
Other International	314,879		34,116		24,451		373,446
Total revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828

Nine Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Primary Geographic Markets
United States and Canada	$	1,485,545	$	131,215	$	146,816	$	59,419	$	1,822,995
Europe, Middle East and Africa	551,070		57,163		89,783		38,369		736,385
Other International	271,811		26,103		21,507		7,774		327,195
Total revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575


(1)	Revenue is reported based on where the sale is fulfilled.


(2)	During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

The Company’s revenue is generated primarily through direct sales to clients by domestic and international sales forces and a network of independent international sales agents. Most of the Company’s products and services are provided on an integrated worldwide basis and, because of this integrated delivery approach, it is not practical to precisely separate our revenue by geographic location. Accordingly, revenue information presented in the above tables is based on internal allocations, which involve certain management estimates and judgments.

By Timing of Revenue Recognition (1)

Three Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Timing of Revenue Recognition
Transferred over time (2)	$	769,718	$	—	$	77,570	$	847,288
Transferred at a point in time (3)	71,280		66,286		15,648		153,214
Total revenues	$	840,998	$	66,286	$	93,218	$	1,000,502

Three Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Timing of Revenue Recognition
Transferred over time (2)	$	709,496	$	—	$	69,755	$	8,800	$	788,051
Transferred at a point in time (3)	64,692		57,141		8,997		2,793		133,623
Total revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674

Nine Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Timing of Revenue Recognition
Transferred over time (2)	$	2,276,783	$	—	$	235,641	$	2,512,424
Transferred at a point in time (3)	215,644		259,392		54,368		529,404
Total revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828

Nine Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Timing of Revenue Recognition
Transferred over time (2)	$	2,119,393	$	—	$	220,838	$	86,667	$	2,426,898
Transferred at a point in time (3)	189,033		214,481		37,268		18,895		459,677
Total revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575


(1)	During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

(2)

Research revenues were recognized in connection with performance obligations that were satisfied over time using a time-elapsed output method to measure progress. Consulting revenues were recognized over time using labor hours as an input measurement basis. During 2018, Other revenues were recognized using either a time-elapsed output method, performance-based milestone approach or labor hours, depending on the nature of the underlying customer contract.


(3)	The revenues in this category were recognized in connection with performance obligations that were satisfied at the point in time the contractual deliverables were provided to the customer.

Performance Obligations — For customer contracts that are greater than one year in duration, the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied (or partially unsatisfied) as of September 30, 2019 was approximately $2.9 billion. The Company expects to recognize $514.2 million, $1,592.9 million and $750.1 million of this revenue (most of which pertains to Research) during the remainder of 2019, the year ending December 31, 2020 and thereafter, respectively. The Company applies an available practical expedient that is permitted under ASC Topic 606 and, accordingly, it does not disclose such performance obligation information for customer contracts that have original durations of one year or less. Our performance obligations for contracts meeting this ASC Topic 606 disclosure exclusion primarily include: (i) stand-ready services under Research subscription contracts; (ii) holding conferences and meetings where attendees and exhibitors can participate; and (iii) providing

customized Consulting solutions for clients under fixed fee and time and materials engagements. The remaining duration of these performance obligations is generally less than one year, which aligns with the period that the parties have enforceable rights and obligations under the affected contracts.

Customer Contract Assets and Liabilities — The timing of the recognition of revenue, and the amount and timing of our billings and cash collections, as well as upfront customer payments, result in the recording of both assets and liabilities on our Condensed Consolidated Balance Sheets. The table below provides information regarding certain of the Company’s balance sheet accounts that pertain to its contracts with customers (in thousands).



	September 30,		December 31,
	2019		2018
Assets:
Fees receivable, gross (1)	$	1,036,120	$	1,262,818

Contract assets recorded in Prepaid expenses and other current assets (2)	$	24,905	$	26,119

Contract liabilities:
Deferred revenues (current liability) (3)	$	1,803,135	$	1,745,244
Non-current deferred revenues recorded in Other liabilities (3)	15,784		21,194
Total contract liabilities	$	1,818,919	$	1,766,438


(1)	Fees receivable represent an unconditional right of payment from our customers and include both billed and unbilled amounts.


(2)	Contract assets represent recognized revenue for which we do not have an unconditional right to payment as of the balance sheet date because the project may be subject to a progress billing milestone or some other billing restriction.


(3)	Deferred revenues represent amounts (i) for which the Company has received an upfront customer payment or (ii) that pertain to recognized fees receivable. Both situations occur before the completion of our performance obligation(s).

The Company recognized revenue of $675.2 million and $642.0 million during the three months ended September 30, 2019 and 2018, respectively, and $1,312.3 million and $1,164.2 million during the nine months ended September 30, 2019 and 2018, respectively, that was attributable to deferred revenues that were recorded at the beginning of each such period. Those amounts primarily consisted of (i) Research revenues and, in the 2018 periods, Other revenues that were recognized ratably as control of the goods or services passed to the customer and (ii) Conferences revenue pertaining to conferences and meetings that occurred during the reporting periods. During each of the three and nine months ended September 30, 2019 and 2018, the Company did not record any material impairments related to its contract assets. The Company does not typically recognize revenue from performance obligations satisfied in prior periods.

Acquisition and divestiture activities. The Company recognized $1.7 million and $17.1 million of Acquisition and integration charges during the three months ended September 30, 2019 and 2018, respectively, and $4.2 million and $96.3 million during the nine months ended September 30, 2019 and 2018, respectively. Acquisition and integration charges reflect additional costs and expenses resulting from our acquisitions and include, among other items, professional fees, severance and stock-based compensation charges. During the nine months ended September 30, 2018, the charges included $51.4 million of exit costs for certain acquisition-related office space in Arlington, Virginia that the Company did not occupy (such activity for the three months ended September 30, 2018 was nominal). The Company recorded no exit costs for facilities during the three and nine months ended September 30, 2019. Although the Company did not complete any business acquisitions during the nine months ended September 30, 2019 or 2018, it paid $2.3 million and $15.9 million of restricted cash in 2019 and 2018, respectively, for deferred consideration from pre-2018 acquisitions.

During the nine months ended September 30, 2018, the Company completed the divestitures of three non-core businesses that had been reported as part of its Other segment. These businesses were acquired as part of the CEB Inc. acquisition in 2017. Revenue from those divested operations was $8.6 million and $97.0 million during the three and nine months ended September 30, 2018, respectively, while the gross contribution was $4.9 million and $60.1 million during the three and nine months ended September 30, 2018, respectively. Also during 2018, the Company sold other miscellaneous assets acquired in the CEB Inc. transaction. For the nine months ended September 30, 2018, the Company recorded $520.7 million in total net cash proceeds from these sales and a net pretax gain of $38.5 million. During the nine months ended September 30, 2019, the Company recorded a pretax Loss from divested operations of $2.1 million, primarily due to adjustments of certain working capital balances related to its 2018 divestitures.

Fair value adjustment - equity security. During both the three and nine months ended September 30, 2019, the Company recognized unrealized appreciation of $9.1 million related to a minority equity investment that we sold in October 2019. That benefit was

recorded in Other income (expense), net in the accompanying Condensed Consolidated Statements of Operations. The minority equity investment’s estimated fair value of $14.1 million was included in Prepaid expenses and other current assets in the accompanying Condensed Consolidated Balance Sheet as of September 30, 2019. Our valuation of such investment was based on certain observable inputs, which the Company considers to be Level 2 inputs under the valuation hierarchy that is described in Note 10 - Fair Value Disclosures.

Cash and cash equivalents and restricted cash. For the nine months ended September 30, 2019, the beginning of period cash and cash equivalents and restricted cash balance of $158.7 million in the accompanying Condensed Consolidated Statements of Cash Flows consisted of $156.4 million of cash and cash equivalents and $2.3 million of restricted cash. The restricted cash, which was classified in Prepaid expenses and other current assets in the accompanying Condensed Consolidated Balance Sheets as of December 31, 2018, was paid to a third party in 2019.

Adoption of new accounting standards. The Company adopted the accounting standards described below during the nine months ended September 30, 2019.

Targeted Improvements to Accounting for Hedging Activities — On January 1, 2019, the Company adopted Accounting Standards Update ("ASU") No. 2017-12, "Derivatives and Hedging" ("ASU No. 2017-12"). ASU No. 2017-12 is intended to improve the financial reporting of hedging relationships to better portray the economic results of an entity’s risk management activities in its financial statements. In addition to that main objective, the standard makes certain targeted improvements to simplify the application of the hedge accounting guidance in current U.S. GAAP. The adoption of the standard had no impact on the Company's consolidated financial statements.

Leases — On January 1, 2019, the Company adopted ASU No. 2016-02, "Leases," as amended ("ASU No. 2016-02" or the “new lease standard”). ASU No. 2016-02 significantly changes the accounting for leases because a right-of-use model is now used whereby a lessee must record a right-of-use asset and a related lease liability on its balance sheet for most of its leases. Under ASU No. 2016-02, leases are classified as either operating or finance arrangements, with such classification affecting the pattern of expense recognition in an entity's income statement. For operating leases, ASU No. 2016-02 requires recognition in an entity’s income statement of a single lease cost, calculated so that the cost of the lease is allocated over the lease term, generally on a straight-line basis.

The adoption of ASU No. 2016-02 on January 1, 2019 had a material impact on the Company’s consolidated balance sheet, while the accompanying Condensed Consolidated Statements of Operations and the cash provided by operating activities in the Condensed Consolidated Statements of Cash Flows for the periods ended September 30, 2019 were not materially impacted. Prior to January 1, 2019, the Company recognized lease expense in accordance with then-existing U.S. GAAP under FASB ASC Topic 840, Leases (“prior GAAP”). Although there were significant changes to the Company’s leasing policies and procedures effective January 1, 2019 with the adoption of ASU No. 2016-02, the lease expense recognition patterns under ASU No. 2016-02 and prior GAAP during the periods ended September 30, 2019 and 2018, respectively, were substantively the same. As required by ASU No. 2016-02, the Company's disclosures regarding its leasing activities have been significantly expanded to enable users of our consolidated financial statements to assess the amount, timing and uncertainty of cash flows related to leases. These additional disclosures are included below.

The Company adopted ASU No. 2016-02 on January 1, 2019 using a modified retrospective approach. We elected to use an optional transition method available under ASU No. 2016-02 to record the required cumulative effect adjustments to the opening balance sheet in the period of adoption rather than in the earliest comparative period presented. As such, the Company's historical consolidated financial statements have not been restated.

Under prior GAAP, lease arrangements that met certain criteria were considered operating leases and were not recorded on an entity's balance sheet. Prior to January 1, 2019 and through September 30, 2019, all of the Company’s lease arrangements were accounted for as operating leases. The adoption of ASU No. 2016-02 on January 1, 2019 had a material impact on the Company’s consolidated balance sheet due to the recognition of right-of-use assets of $651.9 million and related lease liabilities of $851.3 million. The Company’s adoption of ASU No. 2016-02 resulted in a net increase of $638.7 million in each of Total Assets and Total Liabilities. The adoption of the new lease standard did not affect Stockholders’ Equity.

In connection with our adoption of ASU No. 2016-02, the Company elected to use certain available practical expedients that were permitted under the new lease standard and made other elections that impact its lease accounting. The Company elected to use these practical expedients in connection with the adoption of ASU No. 2016-02 because, among other things, they simplified the adoption of the new lease standard, streamlined our internal processes and minimized the associated costs. The critical practical expedients and accounting policy elections used by the Company for all classes of leases accounted for under ASU No. 2016-02 were as follows:


•	Existing contracts were not reassessed to determine if they contained leases.


•	Existing leases were not reassessed to determine if their classification should be changed.


•	Initial direct costs for existing leases were not reassessed.


•	Lease components and nonlease components (e.g., common area maintenance charges, etc.) related to a lease arrangement were accounted for as a single lease component for purposes of the recognition and measurement requirements of ASU No. 2016-02.


•	The incremental borrowing rate used for the purpose of measuring each of our lease liabilities was derived by reference to the related lease’s remaining minimum payments and remaining lease term on the date of adopting the new lease standard. We used incremental borrowing rates because we were unable to determine the implicit interest rates in our leases.

Leasing Activities

The Company’s leasing activities are primarily for facilities under cancelable and non-cancelable lease agreements expiring during 2019 and through 2038. These facilities support our executive and administrative activities, research and consulting, sales, systems support, operations, and other functions. The Company also has leases for office equipment and other assets, which are not significant. Certain of these lease agreements include (i) renewal options to extend the lease term for up to five years and/or (ii) options to terminate the agreement within one year. Additionally, certain of the Company’s lease agreements provide standard recurring escalations of lease payments for, among other things, increases in a lessor’s maintenance costs and taxes. Under some lease agreements, the Company may be entitled to allowances, free rent, lessor-financed tenant improvements and other incentives. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants.

Prior to January 1, 2019, the Company recognized lease expense in accordance with prior GAAP. Because both ASU No. 2016-02 and prior GAAP generally recognize operating lease expense on a straight-line basis over the term of the lease arrangement and the Company only has operating lease arrangements, the lease expense recognition patterns under the two accounting methodologies during the three and nine months ended September 30, 2019 and 2018 were substantively the same.

Except for lease arrangements pertaining to facilities, all other operating lease activity is not significant. As such, operating leases for office equipment and other assets (collectively, “other leases”) are: (i) not recognized and measured under the relevant provisions of ASU No. 2016-02; (ii) excluded from the right-of-use assets and related lease liabilities on the accompanying Condensed Consolidated Balance Sheet as of September 30, 2019, as the related amounts are not material; and (iii) excluded from the quantitative disclosures provided below, other than the disclosures under the heading "Lease Disclosures Under Prior GAAP." Other leases are accounted for similar to the guidance for operating leases under prior GAAP, which generally recognizes lease expense on a straight-line basis over the term of the lease arrangement. As a result, the impact of excluding the other leases from the requirements of ASU No. 2016-02 is not significant.

The Company subleases certain office space that it does not intend to occupy. Such sublease arrangements expire during 2019 and through 2032 and primarily relate to facilities in Arlington, Virginia. Certain of the Company’s sublease agreements: (i) include renewal and termination options; (ii) provide for customary escalations of lease payments in the normal course of business; and (iii) grant the subtenant certain allowances, free rent, Gartner-financed tenant improvements and other incentives.

Lease Accounting under ASU No. 2016-02

Under ASU No. 2016-02, a lease is a contract or an agreement, or a part of another arrangement, between two or more parties that, at its inception, creates enforceable rights and obligations that conveys the right to control the use of identified property, plant or equipment for a period of time in exchange for consideration.

Right-of-use assets represent a right to use an underlying asset for the lease term and the related lease liability represents an obligation to make lease payments pursuant to the contractual terms of the lease agreement. Right-of-use assets and lease liabilities are initially recognized on the lease commencement date based on the present value of the lease payments over the lease term. For all of our facilities leases, we account for both lease components and nonlease components (e.g., common area maintenance charges, etc.) as a single lease component when determining the present value of our lease payments. Variable lease payments that are not dependent on an index or a rate are excluded from the determination of our right-of-use assets and lease liabilities and such payments are recognized as expense in the period when the related obligation is incurred.

The Company’s lease agreements do not provide implicit interest rates. Instead, the Company uses an incremental borrowing rate determined on the lease commencement date to calculate the present value of future lease payments. The incremental borrowing rate is calculated for each individual lease and represents the rate of interest that the Company would have to pay to borrow on a collateralized basis (in the currency that the lease is denominated) over a similar term an amount equal to the lease payments in a

similar economic environment. Right-of-use assets also include any initial direct costs incurred by the Company and lease payments made to a lessor on or before the related lease commencement date, less any lease incentives received directly from the lessor.

Certain of the Company’s facility lease agreements include options to extend or terminate the lease. When it is reasonably certain that the Company will exercise a renewal or termination option, the present value of the lease payments for the affected lease is adjusted accordingly. Leases with a term of 12 months or less are accounted for in the same manner as long-term lease arrangements, including any related disclosures. Lease expense for operating leases is generally recognized on a straight-line basis over the lease term, unless the related right-of-use asset was previously impaired.

All of our existing sublease arrangements have been classified as operating leases with sublease income recognized on a straight-line basis over the term of the sublease arrangement. To measure the Company’s periodic sublease income, we elected to use an available practical expedient that is permitted under ASU No. 2016-02 to aggregate nonlease components with the related lease components when (i) the timing and pattern of transfer for the nonlease components and the related lease components are the same and (ii) the lease components, if accounted for separately, would be classified as an operating lease. This practical expedient applies to all of our existing sublease arrangements.

When our lease cost for the term of a sublease exceeds our anticipated sublease income for that same period, we treat that circumstance as an indicator that the carrying amount of our right-of-use asset may not be fully recoverable. In those circumstances, we perform an impairment analysis and, if indicated, we record a charge against earnings to reduce the right-of-use asset to the amount deemed to be recoverable in the future. There were no right-of-use asset impairments during the three and nine months ended September 30, 2019.

On the accompanying Condensed Consolidated Balance Sheet as of September 30, 2019, right-of-use assets are classified and reported in Operating leases - right-of-use assets, and the related lease liabilities are included in Accounts payable and accrued liabilities (current) and Operating leases - liabilities (long-term). On the accompanying Condensed Consolidated Statement of Cash Flows for the nine months ended September 30, 2019, the amortization of right-of-use assets is presented separately and the change in operating lease liabilities is included under Accounts payable, accrued, and other liabilities in the reconciliation of net income to cash provided by operating activities.

Lease Disclosures Under ASU No. 2016-02

All of the Company’s leasing and subleasing activity is recognized in Selling, general and administrative expense in the accompanying Condensed Consolidated Statements of Operations. The table below presents the Company’s net lease cost and certain other information related to the Company’s leasing activities as of and for the periods indicated (dollars in thousands).



Description:	Three Months Ended September 30, 2019			Nine Months Ended September 30, 2019
Operating lease cost (1)	$	35,443		$	106,958
Variable lease cost (2)	3,902			11,517
Sublease income	(10,205		)	(30,767		)
Total lease cost, net (3)	$	29,140		$	87,708

Cash paid for amounts included in the measurement of operating lease liabilities	$	34,294		$	100,172
Cash receipts from sublease arrangements	$	9,000		$	25,131
Right-of-use assets obtained in exchange for new operating lease liabilities	$	38,571		$	67,756

As of September 30, 2019:
Weighted average remaining lease term for operating leases (in years)				10.5
Weighted average discount rate for operating leases				6.9		%


(1)	Included in operating lease cost was $10.8 million and $32.5 million of costs for subleasing activities during the three and nine months ended September 30, 2019, respectively.


(2)	These amounts are primarily variable lease and nonlease costs that were not fixed at the lease commencement date or are dependent on something other than an index or a rate.


(3)	The Company did not capitalize any operating lease costs during the three and nine months ended September 30, 2019.

As of September 30, 2019, the (i) maturities of operating lease liabilities under non-cancelable arrangements and (ii) estimated future sublease cash receipts from non-cancelable arrangements were as follows (in thousands):



	Operating			Sublease
	Lease			Cash
Period ending December 31,	Payments			Receipts
2019 (remaining three months)	$	35,125		$	9,344
2020	133,534			40,534
2021	126,602			42,918
2022	121,021			43,587
2023	115,034			44,469
Thereafter	693,901			177,741
Total future minimum operating lease payments and estimated sublease cash receipts (1)	1,225,217			$	358,593
Imputed interest	(368,485		)
Total per the Condensed Consolidated Balance Sheet	$	856,732


(1)	Approximately 84% of the operating lease payments pertain to properties in the United States.

The table below indicates where the discounted operating lease payments from the above table are classified in the accompanying Condensed Consolidated Balance Sheet as of September 30, 2019 (in thousands).



Description:
Accounts payable and accrued liabilities	$	80,170
Operating leases - liabilities	776,562
Total operating lease liabilities per the Condensed Consolidated Balance Sheet	$	856,732

As of September 30, 2019, the Company had additional operating leases for facilities that have not yet commenced. These operating leases, which aggregated $146.6 million of undiscounted lease payments, are scheduled to commence between 2019 and 2021 with lease terms of up to ten years.

Lease Disclosures Under Prior GAAP

Based on the Company's selected method of adoption for ASU No. 2016-02, the prior GAAP disclosures presented below are required in our Condensed Consolidated Financial Statements.

As of December 31, 2018, future minimum annual cash payments under non-cancelable operating lease agreements for facilities, office equipment and other assets, which expire during 2019 and through 2038, were as follows (in thousands):



Year ending December 31,
2019	$	130,991
2020	121,802
2021	118,945
2022	111,117
2023	106,113
Thereafter	689,360
Total minimum lease payments (1)	$	1,278,328

(1) Excludes approximately $372.0 million of sublease income.

Accounting standards issued but not yet adopted. The FASB has issued accounting standards that have not yet become effective and may impact the Company’s consolidated financial statements or related disclosures in future periods. Those standards and their potential impact are discussed below.

Accounting standards effective in 2020

Implementation Costs in a Cloud Computing Arrangement — In August 2018, the FASB issued ASU No. 2018-15, "Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract" ("ASU No. 2018-15"). ASU No. 2018-15 aligns the requirements for capitalizing implementation costs incurred in a cloud computing arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. Costs that are capitalized under ASU No. 2018-15 will be expensed over the term of the cloud computing arrangement. ASU No. 2018-15 is effective for Gartner on January 1, 2020, with early adoption permitted. ASU No. 2018-15 may be adopted using either a retroactive or prospective method. The adoption of ASU No. 2018-15 is currently not expected to have a material impact on the Company's consolidated financial statements; however, the new standard will change the classification of certain items on the Company's consolidated balance sheets, statements of operations and statements of cash flows in future periods.

Defined Benefit Plan Disclosures — In August 2018, the FASB issued ASU No. 2018-14, "Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans" ("ASU No. 2018-14"). ASU No. 2018-14, which is part of the FASB's broader disclosure framework project, modifies and supplements the current U.S. GAAP annual disclosure requirements for employers that sponsor defined benefit pension plans. ASU No. 2018-14 is effective for Gartner for the year ending December 31, 2020, with early adoption permitted. ASU No. 2018-14 must be adopted on a retroactive basis and applied to each comparative period presented in an entity's financial statements. The adoption of ASU No. 2018-14 is currently not expected to have a material impact on the Company's financial statement disclosures.

Fair Value Measurement Disclosures — In August 2018, the FASB issued ASU No. 2018-13, "Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement" ("ASU No. 2018-13"). ASU No. 2018-13, which is part of the FASB's broader disclosure framework project, modifies and supplements the current U.S. GAAP disclosure requirements pertaining to fair value measurements, with an emphasis on Level 3 disclosures of the valuation hierarchy. ASU No. 2018-13 is effective for Gartner on January 1, 2020, with early adoption permitted. The adoption of ASU No. 2018-13 is currently not expected to have a material impact on the Company's financial statement disclosures.

Goodwill Impairment — In January 2017, the FASB issued ASU No. 2017-04, "Intangibles—Goodwill and Other - Simplifying the Test for Goodwill Impairment" ("ASU No. 2017-04"). ASU No. 2017-04 simplifies the determination of the amount of goodwill to be potentially charged off by eliminating Step 2 of the goodwill impairment test under current U.S. GAAP. ASU No. 2017-04 is effective for Gartner on January 1, 2020. The adoption of ASU No. 2017-04 is currently not expected to have a material impact on the Company's consolidated financial statements.

Financial Instrument Credit Losses — In June 2016, the FASB issued ASU No. 2016-13, "Financial Instruments—Credit Losses" ("ASU No. 2016-13"). ASU No. 2016-13 amends the current financial instrument impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables. ASU No. 2016-13 is effective for Gartner on January 1, 2020, with early adoption permitted. The adoption of ASU No. 2016-13 is currently not expected to have a material impact on the Company's consolidated financial statements.

The FASB continues to work on a number of other accounting standards which, if issued, could materially impact the Company's accounting policies and disclosures in future periods. As these standards have not yet been issued, the effective dates and potential impact are unknown.

Computation of Earnings Per Share

9 Months Ended

Sep. 30, 2019

Earnings Per Share [Abstract]

Computation of Earnings Per Share

Basic earnings per share (“EPS”) is computed by dividing net income by the weighted average number of shares of Common Stock outstanding during the period. Diluted EPS reflects the potential dilution of securities that could share in earnings. When the impact of common share equivalents is anti-dilutive, they are excluded from the calculation.

The table below sets forth the calculation of basic and diluted income per share for the periods indicated (in thousands, except per share data).



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2019		2018		2019		2018
Numerator:
Net income used for calculating basic and diluted income per common share	$	41,388	$	11,753	$	165,589	$	38,436

Denominator:
Weighted average common shares used in the calculation of basic income per share	89,846		90,854		89,947		90,969
Common stock equivalents associated with stock-based compensation plans (1)	1,041		1,294		1,142		1,275
Shares used in the calculation of diluted income per share	90,887		92,148		91,089		92,244

Basic income per share	$	0.46	$	0.13	$	1.84	$	0.42
Diluted income per share	$	0.46	$	0.13	$	1.82	$	0.42

(1)

Certain common stock equivalents were not included in the computation of diluted income per share because the effect would have been anti-dilutive. These common share equivalents totaled less than 0.2 million for each of the three and nine months ended September 30, 2018. For the three and nine months ended September 30, 2019, approximately 0.3 million and 0.2 million, respectively, of common stock equivalents were excluded from the calculation of diluted income per share because they were anti-dilutive.

Stock-Based Compensation

9 Months Ended

Sep. 30, 2019

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation

The Company grants stock-based compensation awards as an incentive for employees and directors to contribute to the Company’s long-term success. The Company currently awards stock-settled stock appreciation rights, service-based and performance-based restricted stock units, and common stock equivalents. As of September 30, 2019, the Company had 4.4 million shares of its common stock, par value $.0005 per share, (the “Common Stock”) available for stock-based compensation awards under its 2014 Long-Term Incentive Plan.

The Company accounts for stock-based compensation awards in accordance with FASB ASC Topics 505 and 718 and SEC Staff Accounting Bulletins No. 107 and No. 110. Stock-based compensation expense for equity awards is based on the fair value of the award on the date of grant. The Company recognizes stock-based compensation expense over the period that the related service is performed, which is generally the same as the vesting period of the underlying award. Currently, the Company issues treasury shares upon the exercise, release or settlement of stock-based compensation awards.

Determining the appropriate fair value model and calculating the fair value of stock-based compensation awards requires the use of certain subjective assumptions, including the expected life of a stock-based compensation award and Common Stock price volatility. In addition, determining the appropriate periodic stock-based compensation expense requires management to estimate the likelihood of the achievement of certain performance targets. The assumptions used in calculating the fair values of stock-based compensation awards and the related periodic expense represent management’s best estimates, which involve inherent uncertainties and the application of judgment. As a result, if circumstances change and the Company deems it necessary in the future to modify the assumptions it made or to use different assumptions, or if the quantity and nature of the Company’s stock-based compensation awards changes, then the amount of expense may need to be adjusted and future stock-based compensation expense could be materially different from what has been recorded in the current period.

Stock-Based Compensation Expense

The Company recognized the following stock-based compensation expense by award type and expense category line item during the periods indicated (in millions):



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
Award type	2019		2018		2019		2018
Stock appreciation rights	$	1.0	$	0.8	$	5.8	$	5.6
Restricted stock units	11.8		9.8		51.5		49.9
Common stock equivalents	0.2		0.1		0.6		0.5
Total (1)	$	13.0	$	10.7	$	57.9	$	56.0



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
Expense category line item	2019		2018		2019		2018
Cost of services and product development	$	6.2	$	4.7	$	23.7	$	22.8
Selling, general and administrative	6.7		5.7		33.8		31.4
Acquisition and integration charges (2)	0.1		0.3		0.4		1.8
Total (1)	$	13.0	$	10.7	$	57.9	$	56.0

(1) Includes a charge of $0.4 million and a credit of $0.3 million during the three months ended September 30, 2019 and 2018, respectively, and charges of $21.8 million and $19.6 million during the nine months ended September 30, 2019 and 2018, respectively, for awards to retirement-eligible employees. Those awards vest on an accelerated basis.

(2) Includes charges related to an acquisition and the related integration process.

As of September 30, 2019, the Company had $100.0 million of total unrecognized stock-based compensation cost, which is expected to be expensed over the remaining weighted average service period of approximately 2.5 years.

Stock-Based Compensation Awards

The disclosures presented below provide information regarding the Company’s stock-based compensation awards, all of which have been classified as equity awards in accordance with FASB ASC Topic 505.

Stock Appreciation Rights

Stock-settled stock appreciation rights ("SARs") permit the holder to participate in the appreciation of the value of the Common Stock. After the applicable vesting criteria have been satisfied, SARs are settled in shares of Common Stock upon exercise by the employee. SARs vest ratably over a four-year service period and expire seven years from the date of grant. The fair value of a SARs award is recognized as compensation expense on a straight-line basis over four years. SARs have only been awarded to the Company’s executive officers.

When SARs are exercised, the number of shares of Common Stock issued is calculated as follows: (1) the total proceeds from the exercise of the SARs award (calculated as the closing price of the Common Stock as reported on the New York Stock Exchange on the date of exercise less the exercise price of the SARs award, multiplied by the number of SARs exercised) is divided by (2) the closing price of the Common Stock on the date of exercise. Upon exercise, the Company withholds a portion of the shares of the Common Stock to satisfy statutory tax withholding requirements. SARs recipients do not have any stockholder rights until the shares of Common Stock are issued in respect of the award, which is subject to the prior satisfaction of the vesting and other criteria relating to such grants.

The table below summarizes changes in SARs outstanding during the nine months ended September 30, 2019.



	Stock Appreciation Rights ("SARs") (in millions)		Per Share Weighted Average Exercise Price		Per Share Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term (Years)
Outstanding at December 31, 2018	1.2		$	89.45	$	19.88	4.33
Granted	0.3		143.23		32.62		6.36
Forfeited	(0.1	)	118.31		26.52		n/a
Exercised	(0.1	)	70.54		16.64		n/a
Outstanding at September 30, 2019 (1) (2)	1.3		$	100.54	$	22.43	4.18
Vested and exercisable at September 30, 2019 (2)	0.7		$	83.36	$	18.46	3.11

n/a = not applicable

(1) As of September 30, 2019, 0.6 million of the total SARs outstanding were unvested. The Company expects that substantially all of those unvested awards will vest in future periods.

(2) As of September 30, 2019, the total SARs outstanding had an intrinsic value of $56.9 million. On such date, SARs vested and exercisable had an intrinsic value of $42.1 million.

The fair value of a SARs award is determined on the date of grant using the Black-Scholes-Merton valuation model with the following weighted average assumptions:



	Nine Months Ended
	September 30,
	2019		2018
Expected dividend yield (1)	—	%	—	%
Expected stock price volatility (2)	21	%	21	%
Risk-free interest rate (3)	2.5	%	2.5	%
Expected life in years (4)	4.6		4.5


(1)	The expected dividend yield assumption was based on both the Company's historical and anticipated dividend payouts. Historically, the Company has not paid cash dividends on its Common Stock.


(2)	The determination of expected stock price volatility was based on both historical Common Stock prices and implied volatility from publicly traded options in the Common Stock.


(3)	The risk-free interest rate was based on the yield of a U.S. Treasury security with a maturity similar to the expected life of the award.


(4)	The expected life represents the Company’s estimate of the weighted average period of time the SARs are expected to be outstanding (that is, the period between the service inception date and the expected exercise date).

Restricted Stock Units

Restricted stock units ("RSUs") give the awardee the right to receive shares of Common Stock when the vesting conditions are met and certain restrictions lapse. Each RSU that vests entitles the awardee to one share of Common Stock. RSU awardees do not have any of the rights of a Gartner stockholder, including voting rights and the right to receive dividends and distributions, until the shares are released. The fair value of an RSU award is determined on the date of grant based on the closing price of the Common Stock as reported on the New York Stock Exchange on that date. Service-based RSUs vest ratably over four years and are expensed on a straight-line basis over the vesting period. Performance-based RSUs are subject to the satisfaction of both performance and service conditions, vest ratably over four years and are expensed on an accelerated basis over the vesting period.

The table below summarizes the changes in RSUs outstanding during the nine months ended September 30, 2019.



	Restricted Stock Units ("RSUs") (in millions)		Per Share Weighted Average Grant Date Fair Value
Outstanding at December 31, 2018	1.4		$	101.75
Granted (1)	0.5		139.84
Vested and released	(0.5	)	97.13
Forfeited	(0.1	)	115.15
Outstanding at September 30, 2019 (2) (3)	1.3		$	118.94

(1)

The 0.5 million of RSUs granted during the nine months ended September 30, 2019 consisted of 0.2 million of performance-based RSUs awarded to executives and 0.3 million of service-based RSUs awarded to non-executive employees and non-management board members. The performance-based awards include RSUs in final settlement of 2018 grants and approximately 0.1 million of RSUs representing the target amount of the grant for the year ending December 31, 2019 that is tied to an increase in Gartner's total contract value for 2019. The number of performance-based RSUs that will ultimately be awarded for 2019 ranges from 0% to 200% of the target amount and will be finalized based on the actual increase in Gartner's total contract value for 2019 as measured on December 31, 2019. If the specified minimum level of achievement is not met, the performance-based RSUs pertaining to 2019 will be forfeited in their entirety and any previously recorded compensation expense will be reversed.


(2)	The Company expects that substantially all of the RSUs outstanding will vest in future periods.


(3)	As of September 30, 2019, the weighted-average remaining contractual term of the RSUs outstanding was approximately 1.3 years.

Common Stock Equivalents

Common stock equivalents ("CSEs") are convertible into Common Stock. Each CSE entitles the holder to one share of Common Stock. Members of our Board of Directors receive their directors’ fees in CSEs unless they opt to receive up to 50% of those fees in cash. Generally, CSEs have no defined term and are converted into shares of Common Stock when service as a director terminates unless the director has elected an accelerated release. The fair value of a CSE award is determined on the date of grant based on the closing price of the Common Stock as reported on the New York Stock Exchange on that date. CSEs vest immediately and, as a result, they are recorded as expense on the date of grant.

The table below summarizes the changes in CSEs outstanding during the nine months ended September 30, 2019.



	Common Stock Equivalents ("CSEs")		Per Share Weighted Average Grant Date Fair Value
Outstanding at December 31, 2018	109,780		$	24.96
Granted	3,410		152.58
Converted to shares of Common Stock upon grant	(2,199	)	146.28
Outstanding at September 30, 2019	110,991		$	26.48

Employee Stock Purchase Plan

The Company has an employee stock purchase plan (the “ESP Plan”) wherein eligible employees are permitted to purchase shares of Common Stock through payroll deductions, which may not exceed 10% of an employee’s compensation, or $23,750 in any calendar year, at a price equal to 95% of the closing price of the Common Stock as reported on the New York Stock Exchange at the end of each offering period. As of September 30, 2019, the Company had 0.6 million shares available for purchase under the ESP Plan. The ESP Plan is considered non-compensatory under FASB ASC Topic 718 and, as a result, the Company does not record stock-based compensation expense for employee share purchases. The Company received $13.2 million and $11.1 million in cash from employee share purchases under the ESP Plan during the nine months ended September 30, 2019 and 2018, respectively.

Segment Information

9 Months Ended

Sep. 30, 2019

Segment Reporting [Abstract]

Segment Information

Our products and services are delivered through three segments – Research, Conferences and Consulting, as described below.

•

Research provides trusted, objective insights and advice on the mission-critical priorities of leaders across all functional areas of the enterprise through research and other reports, briefings, proprietary tools, access to our analysts and advisors, peer networking services and membership programs that enable our clients to make better decisions. Our traditional strengths in IT, marketing and supply chain research are supplemented by best practice and talent management research insights across a range of business functions, including human resources, sales, legal and finance.


•	Conferences provides business professionals across an organization the opportunity to learn, share and network. From our flagship Chief Information Officer conference Gartner IT Symposium, to industry-leading conferences focused on specific business roles and topics, to member-driven sessions, our offerings enable attendees to experience the best of Gartner insight and advice live.


•	Consulting provides customized solutions to unique client needs through on-site, day-to-day support, as well as proprietary tools for measuring and improving IT performance with a focus on cost, performance, efficiency and quality.

The Company evaluates segment performance and allocates resources based on gross contribution margin. Gross contribution, as presented in the table below, is defined as operating income or loss excluding certain Cost of services and product development expenses, Selling, general and administrative expenses, Depreciation, Amortization of intangibles, and Acquisition and integration charges. Certain bonus and fringe benefit costs included in consolidated Cost of services and product development are not allocated to segment expense. The accounting policies used by the reportable segments are the same as those used by the Company. There are no intersegment revenues. The Company does not identify or allocate assets, including capital expenditures, by reportable segment. Accordingly, assets are not reported by segment because the information is not available by segment and is not reviewed in the evaluation of segment performance or in making decisions regarding the allocation of resources.

The tables below present information about the Company’s reportable segments for the periods indicated (in thousands) (1).



Three Months Ended September 30, 2019	Research		Conferences		Consulting		Consolidated
Revenues	$	840,998	$	66,286	$	93,218	$	1,000,502
Gross contribution	582,502		27,465		26,538		636,505
Corporate and other expenses							(567,358		)
Operating income							$	69,147



Three Months Ended September 30, 2018	Research		Conferences		Consulting		Other		Consolidated
Revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674
Gross contribution	534,911		25,047		18,419		6,927		585,304
Corporate and other expenses									(532,580		)
Operating income									$	52,724



Nine Months Ended September 30, 2019	Research		Conferences		Consulting		Consolidated
Revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828
Gross contribution	1,729,967		126,910		89,493		1,946,370
Corporate and other expenses							(1,712,422		)
Operating income							$	233,948



Nine Months Ended September 30, 2018	Research		Conferences		Consulting		Other		Consolidated
Revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575
Gross contribution	1,599,277		104,698		76,236		65,075		1,845,286
Corporate and other expenses									(1,715,177		)
Operating income									$	130,109

(1) During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

The table below provides a reconciliation of total segment gross contribution to net income for the periods indicated (in thousands).



	Three Months Ended					Nine Months Ended
	September 30,					September 30,
	2019		2018			2019			2018
Total segment gross contribution	$	636,505	$	585,304		$	1,946,370		$	1,845,286
Costs and expenses:
Cost of services and product development - unallocated (1)	1,059		(258		)	4,242			19,669
Selling, general and administrative	512,159		447,537			1,545,905			1,396,085
Depreciation and amortization	52,398		68,187			158,119			203,081
Acquisition and integration charges	1,742		17,114			4,156			96,342
Operating income	69,147		52,724			233,948			130,109
Interest expense and other, net	16,049		27,811			66,716			98,454
Gain (loss) from divested operations	—		13,040			(2,075		)	38,500
Provision (benefit) for income taxes	11,710		26,200			(432		)	31,719
Net income	$	41,388	$	11,753		$	165,589		$	38,436

(1)

The unallocated amounts consist of certain bonus and related fringe costs recorded in consolidated Cost of services and product development that are not allocated to segment expense. The Company's policy is to only allocate bonus and related fringe charges to segments for up to 100% of the segment employee's target bonus. Amounts above 100% are absorbed by corporate.

Goodwill and Intangible Assets

9 Months Ended

Sep. 30, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

Goodwill

Goodwill represents the excess of the purchase price of acquired businesses over the estimated fair values of the tangible and identifiable intangible net assets acquired. Evaluations of the recoverability of goodwill are performed in accordance with FASB ASC Topic 350, which requires an annual assessment of potential goodwill impairment at the reporting unit level and whenever events or changes in circumstances indicate that the carrying value of goodwill may not be recoverable. The annual assessment of the recoverability of recorded goodwill can be based on either a qualitative or quantitative assessment or a combination of the two approaches. Both methods utilize estimates which, in turn, require judgments and assumptions regarding future trends and events. As a result, both the precision and reliability of the resulting estimates are subject to uncertainty. If our annual goodwill impairment evaluation determines that the fair value of a reporting unit is less than its related carrying amount, we may recognize an impairment charge. In connection with our most recent annual impairment test of goodwill during the quarter ended September 30, 2019, which indicated no impairment of recorded goodwill, the Company utilized the qualitative approach in assessing the fair values of its reporting units relative to their respective carrying values. Subsequent to completing our 2019 annual impairment test, no events or changes in circumstances were noted that required an interim goodwill impairment test.

The table below presents changes to the carrying amount of goodwill by segment during the nine months ended September 30, 2019 (in thousands).



	Research		Conferences		Consulting			Total
Balance at December 31, 2018 (1)	$	2,638,418	$	187,654	$	97,064		$	2,923,136
Foreign currency translation impact	16,745		24		(198		)	16,571
Balance at September 30, 2019	$	2,655,163	$	187,678	$	96,866		$	2,939,707


(1)	The Company does not have any accumulated goodwill impairment losses.

Finite-Lived Intangible Assets

The tables below present reconciliations of the carrying amounts of the Company's finite-lived intangible assets as of the dates indicated (in thousands).



September 30, 2019	Customer Relationships			Software			Content			Other			Total
Gross cost at December 31, 2018	$	1,131,656		$	110,701		$	98,842		$	51,662		$	1,392,861
Intangible assets fully amortized	—			—			(85,900		)	(18,680		)	(104,580		)
Foreign currency translation impact	(9,810		)	(303		)	(2		)	(106		)	(10,221		)
Gross cost	1,121,846			110,398			12,940			32,876			1,278,060
Accumulated amortization (1)	(255,139		)	(55,609		)	(9,973		)	(21,026		)	(341,747		)
Balance at September 30, 2019	$	866,707		$	54,789		$	2,967		$	11,850		$	936,313



December 31, 2018	Customer Relationships			Software			Content			Other			Total
Gross cost	$	1,131,656		$	110,701		$	98,842		$	51,662		$	1,392,861
Accumulated amortization (1)	(184,918		)	(38,901		)	(92,717		)	(33,760		)	(350,296		)
Balance at December 31, 2018	$	946,738		$	71,800		$	6,125		$	17,902		$	1,042,565

(1) Finite-lived intangible assets are amortized using the straight-line method over the following periods: Customer relationships—4 to 13 years; Software—3 to 7 years; Content—1.5 to 5 years; and Other—2 to 11 years.

Amortization expense related to finite-lived intangible assets was $31.7 million and $50.9 million during the three months ended September 30, 2019 and 2018, respectively, and $97.5 million and $152.6 million during the nine months ended September 30, 2019 and 2018, respectively. The estimated future amortization expense by year for finite-lived intangible assets is as follows (in thousands):



2019 (remaining three months)	$	31,812
2020	122,864
2021	102,493
2022	92,989
2023	92,989
Thereafter	493,166
	$	936,313

Debt

9 Months Ended

Sep. 30, 2019

Debt Disclosure [Abstract]

Debt

2016 Credit Agreement

The Company has a credit facility that currently provides for a $1.5 billion Term loan A facility and a $1.2 billion revolving credit facility (the "2016 Credit Agreement"). The 2016 Credit Agreement contains certain customary restrictive loan covenants, including, among others, financial covenants that apply a maximum leverage ratio and a minimum interest expense coverage ratio, and covenants limiting Gartner’s ability to incur indebtedness, grant liens, make acquisitions, merge, dispose of assets, pay dividends, repurchase stock, make investments and enter into certain transactions with affiliates. The Company was in full compliance with the covenants as of September 30, 2019.

The Term loan A facility is being repaid in 16 consecutive quarterly installments that commenced on June 30, 2017, plus a final payment to be made on March 20, 2022. The revolving credit facility may be borrowed, repaid, and re-borrowed through March 20, 2022, at which time all amounts must be repaid. Amounts borrowed under the Term loan A facility and the revolving credit facility bear interest at a rate equal to, at the Company's option, either:

(i) the greatest of: (x) the Administrative Agent’s prime rate; (y) the rate calculated by the New York Federal Reserve Bank for federal funds transactions plus 1/2 of 1%; and (z) the eurodollar rate (adjusted for statutory reserves) plus 1%, in each case plus

a margin equal to between 0.125% and 1.50%, depending on Gartner’s consolidated leverage ratio as of the end of the four consecutive fiscal quarters most recently ended; or

(ii) the eurodollar rate (adjusted for statutory reserves) plus a margin equal to between 1.125% and 2.50%, depending on Gartner’s leverage ratio as of the end of the four consecutive fiscal quarters most recently ended.

Senior Notes

The Company has $800.0 million aggregate principal amount of 5.125% Senior Notes due 2025 (the “Senior Notes”). The Senior Notes were issued at an issue price of 100.0% and bear interest at a fixed rate of 5.125% per annum. Interest on the Senior Notes is payable on April 1 and October 1 of each year. The Senior Notes mature on April 1, 2025.

The Company may redeem some or all of the Senior Notes at any time on or after April 1, 2020 for cash at the redemption prices set forth in the Note Indenture, plus accrued and unpaid interest to, but not including, the redemption date. Prior to April 1, 2020, the Company may redeem up to 40% of the aggregate principal amount of the Senior Notes with the proceeds of certain equity offerings at a redemption price of 105.125% plus accrued and unpaid interest to, but not including, the redemption date. In addition, the Company may redeem some or all of the Senior Notes prior to April 1, 2020 at a redemption price of 100% of the principal amount of the Senior Notes plus accrued and unpaid interest to, but not including, the redemption date, plus a “make-whole” premium. If the Company experiences certain kinds of changes of control, it will be required to offer to purchase the Senior Notes at a price equal to 101% of the principal amount thereof plus accrued and unpaid interest.

Outstanding Borrowings

The table below summarizes the Company’s total outstanding borrowings as of the dates indicated (in thousands).



	September 30,			December 31,
Description:	2019			2018
2016 Credit Agreement - Term loan A facility (1)	$	1,280,813		$	1,355,062
2016 Credit Agreement - Revolving credit facility (1), (2)	120,000			155,000
Senior Notes (3)	800,000			800,000
Other (4)	6,667			2,030
Principal amount outstanding (5)	2,207,480			2,312,092
Less: deferred financing fees (6)	(25,540		)	(30,405		)
Net balance sheet carrying amount	$	2,181,940		$	2,281,687


(1)	The contractual annualized interest rate as of September 30, 2019 on the Term loan A facility and the revolving credit facility was 3.54%, which consisted of a floating eurodollar base rate of 2.04% plus a margin of 1.50%. However, the Company has interest rate swap contracts that effectively convert the floating eurodollar base rates on amounts outstanding to a fixed base rate.


(2)	The Company had approximately $1.1 billion of available borrowing capacity on the revolver (not including the expansion feature) as of September 30, 2019.


(3)	Consists of $800.0 million principal amount of Senior Notes outstanding. The Senior Notes pay a fixed rate of 5.125% and mature on April 1, 2025.

(4)

Consists of two State of Connecticut economic development loans. One of the loans originated in 2012, has a 10-year maturity and the outstanding balance of $1.7 million as of September 30, 2019 bears interest at a fixed rate of 3.00%. In connection with an expansion project at its Stamford, Connecticut headquarters, the Company borrowed $5.0 million during the nine months ended September 30, 2019 under a financial assistance program offered by the State of Connecticut. This second loan has a 10-year maturity and bears interest at a fixed rate of 1.75%. Principal and interest payments are deferred for the first seven years. The loan has a provision whereby some or all of the $5.0 million principal may be forgiven if the Company meets certain employment targets in the State of Connecticut during the first five years of the loan. Both of these loans may be repaid at any time by the Company without penalty.


(5)	The weighted average annual effective rates on the Company's total debt outstanding for the three and nine months ended September 30, 2019, including the effects of its interest rate swaps discussed below, was 4.00% and 4.01%, respectively.


(6)	Deferred financing fees are being amortized to Interest expense, net over the term of the related debt obligation.

Interest Rate Swaps

The Company has four fixed-for-floating interest rate swap contracts with a total notional value of $1.4 billion that mature through 2025. The Company designates the swaps as accounting hedges of the forecasted interest payments on $1.4 billion of the Company’s variable-rate borrowings. The Company pays base fixed rates on these swaps ranging from 2.13% to 3.04% and in return receives a floating eurodollar base rate on 30-day notional borrowings. The Company accounts for the interest rate swap contracts as cash flow hedges in accordance with FASB ASC Topic 815. Since the swaps hedge forecasted interest payments, changes in the fair values of the swaps are recorded in accumulated other comprehensive income (loss), a component of stockholders' equity, as long as the swaps continue to be highly effective hedges of the designated interest rate risk. All of the Company's swaps were considered highly effective hedges of the forecasted interest payments as of September 30, 2019. The interest rate swaps had a negative unrealized fair value (liability) of $80.2 million as of September 30, 2019, which was deferred and recorded in Accumulated other comprehensive loss, net of tax effect.

Equity

9 Months Ended

Sep. 30, 2019

Stockholders' Equity Note [Abstract]

Equity

Share Repurchase Authorization

The Company has a $1.2 billion board authorization to repurchase the Company's common stock, of which $0.8 billion remained available as of September 30, 2019. The Company may repurchase its common stock from time-to-time in amounts, at prices and in the manner that the Company deems appropriate, subject to the availability of stock, prevailing market conditions, the trading price of the stock, the Company’s financial performance and other conditions. Repurchases may be made through open market purchases (which may include repurchase plans designed to comply with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended), accelerated share repurchases, private transactions or other transactions and will be funded by cash on hand and borrowings. The Company’s share repurchase activity for the periods indicated is presented in the table below.



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2019		2018		2019		2018
Number of shares repurchased (1)	705,800		51,298		929,311		815,001
Cash paid for repurchased shares (in thousands) (2)	$	94,878	$	8,129	$	141,436	$	104,400

(1) The average purchase price for repurchased shares was $134.42 and $140.09 for the three months ended September 30, 2019 and 2018, respectively, and $136.05 and $128.10 for the nine months ended September 30, 2019 and 2018, respectively. The repurchased shares during the three and nine months ended September 30, 2019 and 2018 included purchases for both stock-based compensation awards and open market purchases.

(2) The cash paid for repurchased shares during the nine months ended September 30, 2019 included open market purchases with trade dates in December 2018 that settled in January 2019.

Stockholders' Equity

The tables below provide a reconciliation of changes in the Company's Stockholders' Equity for the periods indicated (in thousands).

Three Months Ended September 30, 2019



	Common Stock		Additional Paid-In Capital		Accumulated Other Comprehensive Loss, Net			Accumulated Earnings		Treasury Stock			Total
Balance at June 30, 2019	$	82	$	1,868,878	$	(73,479	)	$	1,879,633	$	(2,711,312	)	$	963,802
Net income	—		—		—			41,388		—			41,388
Other comprehensive loss	—		—		(7,785		)	—		—			(7,785		)
Issuances under stock plans	—		3,538		—			—		633			4,171
Common share repurchases	—		—		—			—		(94,873		)	(94,873		)
Stock-based compensation expense	—		12,954		—			—		—			12,954
Balance at September 30, 2019	$	82	$	1,885,370	$	(81,264	)	$	1,921,021	$	(2,805,552	)	$	919,657

Three Months Ended September 30, 2018



	Common Stock		Additional Paid-In Capital		Accumulated Other Comprehensive Loss, Net			Accumulated Earnings		Treasury Stock			Total
Balance at June 30, 2018	$	82	$	1,798,075	$	(24,051	)	$	1,659,658	$	(2,512,332	)	$	921,432
Net income	—		—		—			11,753		—			11,753
Other comprehensive income	—		—		1,367			—		—			1,367
Issuances under stock plans	—		1,752		—			—		1,711			3,463
Common share repurchases	—		—		—			—		(7,186		)	(7,186		)
Stock-based compensation expense	—		10,718		—			—		—			10,718
Balance at September 30, 2018	$	82	$	1,810,545	$	(22,684	)	$	1,671,412	$	(2,517,807	)	$	941,548

Nine Months Ended September 30, 2019



	Common Stock		Additional Paid-In Capital		Accumulated Other Comprehensive Loss, Net			Accumulated Earnings		Treasury Stock			Total
Balance at December 31, 2018	$	82	$	1,823,710	$	(39,867	)	$	1,755,432	$	(2,688,600	)	$	850,757
Net income	—		—		—			165,589		—			165,589
Other comprehensive loss	—		—		(41,397		)	—		—			(41,397		)
Issuances under stock plans	—		3,767		—			—		9,481			13,248
Common share repurchases	—		—		—			—		(126,433		)	(126,433		)
Stock-based compensation expense	—		57,893		—			—		—			57,893
Balance at September 30, 2019	$	82	$	1,885,370	$	(81,264	)	$	1,921,021	$	(2,805,552	)	$	919,657

Nine Months Ended September 30, 2018



	Common Stock		Additional Paid-In Capital			Accumulated Other Comprehensive Income (Loss), Net			Accumulated Earnings			Treasury Stock			Total
Balance at December 31, 2017	$	82	$	1,761,383		$	1,508		$	1,647,284		$	(2,426,792	)	$	983,465
Adoption of ASU No. 2018-02 (1)	—		—			591			(591		)	—			—
Adoption of ASU No. 2016-16 (2)	—		—			—			(13,717		)	—			(13,717		)
Net income	—		—			—			38,436			—			38,436
Other comprehensive loss	—		—			(24,783		)	—			—			(24,783		)
Issuances under stock plans	—		(6,856		)	—			—			13,385			6,529
Common share repurchases	—		—			—			—			(104,400		)	(104,400		)
Stock-based compensation expense	—		56,018			—			—			—			56,018
Balance at September 30, 2018	$	82	$	1,810,545		$	(22,684	)	$	1,671,412		$	(2,517,807	)	$	941,548


(1)	On April 1, 2018, the Company early adopted ASU No. 2018-02, "Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income" ("ASU No. 2018-02"), which resulted in a reclassification of $0.6 million of stranded tax amounts related to the U.S. Tax Cuts and Jobs Act of 2017 from Accumulated other comprehensive income (loss), net to Accumulated earnings.

(2)

On January 1, 2018, the Company adopted ASU No. 2016-16, "Intra-Entity Transfers of Assets Other Than Inventory" ("ASU No. 2016-16"). ASU No. 2016-16 accelerates the recognition of taxes on certain intra-entity transactions. As a result of the transition rules under ASU No. 2016-16, certain of the Company's balance sheet income tax accounts pertaining to pre-2018 intra-entity transfers, which aggregated $13.7 million, were reversed against accumulated earnings on January 1, 2018.

Accumulated Other Comprehensive Income (Loss), net ("AOCI/L")

The tables below provide information about the changes in AOCI/L by component and the related amounts reclassified out of AOCI/L to income during the periods indicated (net of tax, in thousands) (1).

Three Months Ended September 30, 2019



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – June 30, 2019	$	(46,990	)	$	(5,655	)	$	(20,834	)	$	(73,479	)
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	(10,285		)	—			3,553			(6,731		)
Reclassifications from AOCI/L to income (2), (3)	(1,094		)	41			—			(1,054		)
Other comprehensive income (loss) for the period	(11,379		)	41			3,553			(7,785		)
Balance – September 30, 2019	$	(58,369	)	$	(5,614	)	$	(17,281	)	$	(81,264	)

Three Months Ended September 30, 2018



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – June 30, 2018	$	16,281		$	(5,750	)	$	(34,582	)	$	(24,051	)
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	969			—			814			1,783
Reclassifications from AOCI/L to income (2), (3), (4)	(619		)	53			150			(416		)
Other comprehensive income (loss) for the period	350			53			964			1,367
Balance – September 30, 2018	$	16,631		$	(5,697	)	$	(33,618	)	$	(22,684	)

Nine Months Ended September 30, 2019



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – December 31, 2018	$	(7,770	)	$	(5,738	)	$	(26,359	)	$	(39,867	)
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	(46,224		)	—			9,078			(37,146		)
Reclassifications from AOCI/L to income (2), (3)	(4,375		)	124			—			(4,251		)
Other comprehensive income (loss) for the period	(50,599		)	124			9,078			(41,397		)
Balance – September 30, 2019	$	(58,369	)	$	(5,614	)	$	(17,281	)	$	(81,264	)

Nine Months Ended September 30, 2018



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – December 31, 2017	$	2,483		$	(5,861	)	$	4,886		1,508
Adoption of ASU No. 2018-02 (5)	591			—			—			591
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	13,748			—			21,656			35,404
Reclassifications from AOCI/L to income (2), (3), (4)	(191		)	164			(60,160		)	(60,187	)
Other comprehensive income (loss) for the period	13,557			164			(38,504		)	(24,783	)
Balance – September 30, 2018	$	16,631		$	(5,697	)	$	(33,618	)	(22,684	)


(1)	Amounts in parentheses represent debits (deferred losses).


(2)	The reclassifications related to interest rate swaps (cash flow hedges) were recorded in Interest expense, net of tax effect. See Note 6 – Debt and Note 9 – Derivatives and Hedging for information regarding the cash flow hedges.


(3)	The reclassifications related to defined benefit pension plans were primarily recorded in Selling, general and administrative expense, net of tax effect. See Note 11 – Employee Benefits for information regarding the Company’s defined benefit pension plans.


(4)	The reclassifications related to foreign currency translation adjustments in 2018 were recorded in Gain (loss) from divested operations. See Note 1 – Business and Basis of Presentation for information regarding our divestitures in 2018.

(5)

On April 1, 2018, the Company early adopted ASU No. 2018-02, "Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income" ("ASU No. 2018-02"), which resulted in a reclassification of $0.6 million of stranded tax amounts related to the U.S. Tax Cuts and Jobs Act of 2017 from AOCI/L to Accumulated earnings.

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The provision for income taxes for the three months ended September 30, 2019 and 2018 was an expense of $11.7 million and $26.2 million, respectively. The provision for income taxes for the nine months ended September 30, 2019 was a benefit of $0.4 million compared to an expense of $31.7 million for the nine months ended September 30, 2018. The effective income tax rate was an expense of 22.1% and 69.0% for the three months ended September 30, 2019 and 2018, respectively. The quarter-over-quarter decrease in the effective income tax rate was primarily attributable to the taxable third quarter 2018 divestiture of the Company’s CEB Challenger training business, which resulted in a greater tax than book gain. The effective income tax rate was a benefit of 0.3% for the nine months ended September 30, 2019 compared to an expense of 45.2% for the nine months ended September 30, 2018. The effective income tax rate for the 2019 nine-month period included a significant benefit from an intercompany sale of certain intellectual property, as discussed below. The favorable impact of that transaction compared to the unfavorable impact from the CEB Challenger training business divestiture during the 2018 nine-month period drove the year-over-year change in the effective income tax rates for the nine-month periods. In April 2019, we completed an intercompany sale of certain intellectual property. As a result, the Company recorded a net tax benefit of approximately $38.1 million during the nine months ended September 30, 2019, which represents the benefits of future tax deductions for amortization of the assets in the acquiring jurisdiction. Our tax planning related to our intellectual property is ongoing and may result in tax rate volatility in the future. The Company had gross unrecognized tax benefits of $87.3 million at September 30, 2019 and $90.3 million at December 31, 2018. It is reasonably possible that gross unrecognized tax benefits will decrease by approximately $2.8 million within the next 12 months due to the anticipated closure of audits and the expiration of certain statutes of limitation. In connection with the Company’s adoption of ASU No. 2016-02 on January 1, 2019, operating leases were recorded on the accompanying Condensed Consolidated Balance Sheet as of September 30, 2019, including the recognition of operating lease liabilities and corresponding right-of-use assets. The corresponding deferred tax assets and deferred tax liabilities were also recorded. The net deferred tax impact was zero. Note 1 — Business and Basis of Presentation provides additional information regarding our leases and the adoption of ASU No. 2016-02.

Derivatives and Hedging

9 Months Ended

Sep. 30, 2019

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivatives and Hedging

The Company enters into a limited number of derivative contracts to mitigate the cash flow risk associated with changes in interest rates on variable-rate debt and changes in foreign exchange rates on forecasted foreign currency transactions. The Company accounts for its outstanding derivative contracts in accordance with FASB ASC Topic 815, which requires all derivatives, including derivatives designated as accounting hedges, to be recorded on the balance sheet at fair value. The tables below provide information regarding the Company’s outstanding derivative contracts as of the dates indicated (in thousands, except for number of contracts).



September 30, 2019
Derivative Contract Type	Number of Contracts	Notional Amounts		Fair Value Asset (Liability), Net (3)			Balance Sheet Line Item	Unrealized Loss Recorded in AOCI/L
Interest rate swaps (1)	4	$	1,400,000	$	(80,233	)	Other liabilities	$	(58,369	)
Foreign currency forwards (2)	40	203,351		(220		)	Accrued liabilities	—
Total	44	$	1,603,351	$	(80,453	)		$	(58,369	)



December 31, 2018
Derivative Contract Type	Number of Contracts	Notional Amounts		Fair Value Asset (Liability), Net (3)			Balance Sheet Line Item	Unrealized Loss Recorded in AOCI/L
Interest rate swaps (1)	7	$	2,100,000	$	(10,681	)	Other liabilities	$	(7,770	)
Foreign currency forwards (2)	135	927,375		(1,942		)	Accrued liabilities	—
Total	142	$	3,027,375	$	(12,623	)		$	(7,770	)


(1)	The interest rate swaps have been designated and are accounted for as cash flow hedges of the forecasted interest payments on borrowings. As a result, changes in the fair values of the swaps are deferred and recorded in AOCI/L, net of tax effect. Note 6 — Debt provides additional information.

(2)

The Company has foreign exchange transaction risk because it typically enters into transactions in the normal course of business that are denominated in foreign currencies that differ from the local functional currency. The Company enters into short-term foreign currency forward exchange contracts to mitigate the cash flow risk associated with changes in foreign currency rates on forecasted foreign currency transactions. These contracts are accounted for at fair value with realized and unrealized gains and losses recognized in Other income (expense), net because the Company does not designate these contracts as hedges for accounting purposes. All of the outstanding foreign currency forward exchange contracts at September 30, 2019 matured before October 31, 2019.


(3)	See Note 10 — Fair Value Disclosures for the determination of the fair values of these instruments.

At September 30, 2019, all of the Company’s derivative counterparties were investment grade financial institutions. The Company did not have any collateral arrangements with its derivative counterparties and none of the derivative contracts contained credit-risk related contingent features. The table below provides information regarding amounts recognized in the accompanying Condensed Consolidated Statements of Operations for derivative contracts for the periods indicated (in thousands).



	Three Months Ended						Nine Months Ended
	September 30,						September 30,
Amount recorded in:	2019			2018			2019			2018
Interest (income) expense, net (1)	$	(1,504	)	$	(851	)	$	(6,015	)	$	(262	)
Other expense, net (2)	4,367			1,140			5,064			2,815
Total expense (income), net	$	2,863		$	289		$	(951	)	$	2,553


(1)	Consists of interest (income) expense from interest rate swap contracts.

(2)

Consists of net realized and unrealized gains and losses on foreign currency forward contracts.

Fair Value Disclosures

9 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Fair Value Disclosures

The Company’s financial instruments include cash equivalents, fees receivable from customers, accounts payable and accruals, all of which are normally short-term in nature. The Company believes that the carrying amounts of these financial instruments reasonably approximate their fair values due to their short-term nature. The Company’s financial instruments also include its outstanding variable-rate borrowings under the 2016 Credit Agreement. The Company believes that the carrying amounts of its variable-rate borrowings reasonably approximate their fair values because the rates of interest on those borrowings reflect current market rates of interest for similar instruments with comparable maturities.

The Company enters into a limited number of derivatives transactions but does not enter into repurchase agreements, securities lending transactions or master netting arrangements. Receivables or payables that result from derivatives transactions are recorded gross in the Company's consolidated balance sheets.

FASB ASC Topic 820 provides a framework for the measurement of fair value and a valuation hierarchy based on the transparency of inputs used in the valuation of assets and liabilities. Classification within the valuation hierarchy is based on the lowest level of input that is significant to the resulting fair value measurement. The valuation hierarchy contains three levels. Level 1 measurements consist of quoted prices in active markets for identical assets or liabilities. Level 2 measurements include significant other observable inputs such as quoted prices for similar assets or liabilities in active markets; identical assets or liabilities in inactive markets; observable inputs such as interest rates and yield curves; and other market-corroborated inputs. Level 3 measurements include significant unobservable inputs, such as internally-created valuation models. The Company does not

currently utilize Level 3 valuation inputs to remeasure any of its assets or liabilities. However, Level 3 inputs may be used by the Company in its required annual impairment review of recorded goodwill. Information regarding the periodic assessment of the Company’s goodwill is included in Note 5 — Goodwill and Intangible Assets. The Company does not typically transfer assets or liabilities between different levels of the valuation hierarchy.

The table below presents the fair value of certain financial assets and liabilities (in thousands).



Description:	September 30, 2019		December 31, 2018
Assets:
Values based on Level 1 inputs:
Deferred compensation plan assets (1)	$	8,985	$	8,956
Total Level 1 inputs	8,985		8,956
Values based on Level 2 inputs:
Deferred compensation plan assets (1)	61,491		57,690
Foreign currency forward contracts (2)	65		1,318
Total Level 2 inputs	61,556		59,008
Total Assets	$	70,541	$	67,964
Liabilities:
Values based on Level 2 inputs:
Deferred compensation plan liabilities (1)	$	74,308	$	68,570
Foreign currency forward contracts (2)	285		3,260
Interest rate swap contracts (3)	80,233		10,681
Senior Notes due 2025 (4)	838,584		776,160
Total Level 2 inputs	993,410		858,671
Total Liabilities	$	993,410	$	858,671

(1)

The Company has a deferred compensation plan for the benefit of certain highly compensated officers, managers and other key employees. The assets consist of investments in money market funds, mutual funds and company-owned life insurance contracts, which are valued based on Level 1 or Level 2 inputs. The related deferred compensation plan liabilities are recorded at fair value, or the estimated amount needed to settle the liability, which the Company considers to be a Level 2 input.


(2)	The Company enters into foreign currency forward exchange contracts to hedge the effects of adverse fluctuations in foreign currency exchange rates (see Note 9 — Derivatives and Hedging). Valuation of these contracts is based on observable foreign currency exchange rates in active markets, which the Company considers to be a Level 2 input.

(3)

The Company has interest rate swap contracts that hedge the risk of variability from interest payments on its borrowings (see Note 6 — Debt). The fair values of interest rate swaps are based on mark-to-market valuations prepared by a third-party broker. Those valuations are based on observable interest rates from recently executed market transactions and other observable market data, which the Company considers to be Level 2 inputs. The Company independently corroborates the reasonableness of the valuations prepared by the third-party broker through the use of an electronic quotation service.

(4)

As discussed in Note 6 — Debt, the Company has $800.0 million of principal amount fixed-rate Senior Notes due in 2025. The estimated fair value of the notes was derived from quoted market prices provided by an independent dealer, which the Company considers to be a Level 2 input.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Employee Benefits	9 Months Ended
Employee Benefits	Sep. 30, 2019
Retirement Benefits [Abstract]
Employee Benefits	Employee Benefits The Company has defined benefit pension plans at several of its international locations. Benefits paid under these plans are based on years of service and level of employee compensation. The Company’s defined benefit pension plans are accounted for in accordance with FASB ASC Topics 715 and 960. Net periodic pension expense was $0.9 million for both the three months ended September 30, 2019 and 2018, and $2.6 million and $2.5 million for the nine months ended September 30, 2019 and 2018, respectively.

Contingencies	9 Months Ended
Contingencies	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Legal Matters. The Company is involved in legal proceedings and litigation arising in the ordinary course of business. We believe that the potential liability, if any, in excess of amounts already accrued from all proceedings, claims and litigation will not have a material effect on our financial position, cash flows or results of operations when resolved in a future period. Indemnifications. The Company has various agreements that may obligate us to indemnify the other party with respect to certain matters. Generally, these indemnification clauses are included in contracts arising in the normal course of business under which we customarily agree to hold the other party harmless against losses arising from a breach of representations related to such matters as title to assets sold and licensed or certain intellectual property rights. It is not possible to predict the maximum potential amount of future payments under these indemnification agreements due to the conditional nature of the Company’s obligations and the unique facts of each particular agreement. Historically, payments made by us under these agreements have not been material. As of September 30, 2019, the Company did not have any material payment obligations under any such indemnification agreements.

Subsequent Event	9 Months Ended
Subsequent Event	Sep. 30, 2019
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On October 1, 2019, the Company acquired 100% of the outstanding membership interests of TOPO Research LLC ("TOPO"), a privately-held company based in Redwood City, California, for an aggregate purchase price of $33 million (subject to certain working capital and other customary post-closing adjustments). TOPO is a subscription-based research and advisory business that helps sales leaders at the world’s fastest-growing companies achieve their growth objectives. The operating results of TOPO are included in the Company's consolidated financial statements beginning on the date of acquisition.

Business and Basis of Presentation (Policies)

9 Months Ended

Sep. 30, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Segments

Basis of presentation

Principles of consolidation

Use of estimates

Revenue Recognition

Disaggregated Revenue — Our disaggregated revenue by reportable segment is presented in the tables below for the periods indicated (in thousands).

By Primary Geographic Market (1), (2)

Three Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Primary Geographic Markets
United States and Canada	$	538,112	$	28,153	$	58,615	$	624,880
Europe, Middle East and Africa	196,121		24,497		26,468		247,086
Other International	106,765		13,636		8,135		128,536
Total revenues	$	840,998	$	66,286	$	93,218	$	1,000,502

Three Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Primary Geographic Markets
United States and Canada	$	502,489	$	22,002	$	45,903	$	8,948	$	579,342
Europe, Middle East and Africa	180,124		25,422		26,255		2,645		234,446
Other International	91,575		9,717		6,594		—		107,886
Total revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674

Nine Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Primary Geographic Markets
United States and Canada	$	1,593,806	$	157,756	$	175,208	$	1,926,770
Europe, Middle East and Africa	583,742		67,520		90,350		741,612
Other International	314,879		34,116		24,451		373,446
Total revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828

Nine Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Primary Geographic Markets
United States and Canada	$	1,485,545	$	131,215	$	146,816	$	59,419	$	1,822,995
Europe, Middle East and Africa	551,070		57,163		89,783		38,369		736,385
Other International	271,811		26,103		21,507		7,774		327,195
Total revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575


(1)	Revenue is reported based on where the sale is fulfilled.


(2)	During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

By Timing of Revenue Recognition (1)

Three Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Timing of Revenue Recognition
Transferred over time (2)	$	769,718	$	—	$	77,570	$	847,288
Transferred at a point in time (3)	71,280		66,286		15,648		153,214
Total revenues	$	840,998	$	66,286	$	93,218	$	1,000,502

Three Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Timing of Revenue Recognition
Transferred over time (2)	$	709,496	$	—	$	69,755	$	8,800	$	788,051
Transferred at a point in time (3)	64,692		57,141		8,997		2,793		133,623
Total revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674

Nine Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Timing of Revenue Recognition
Transferred over time (2)	$	2,276,783	$	—	$	235,641	$	2,512,424
Transferred at a point in time (3)	215,644		259,392		54,368		529,404
Total revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828

Nine Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Timing of Revenue Recognition
Transferred over time (2)	$	2,119,393	$	—	$	220,838	$	86,667	$	2,426,898
Transferred at a point in time (3)	189,033		214,481		37,268		18,895		459,677
Total revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575


(1)	During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

(2)


(3)	The revenues in this category were recognized in connection with performance obligations that were satisfied at the point in time the contractual deliverables were provided to the customer.



	September 30,		December 31,
	2019		2018
Assets:
Fees receivable, gross (1)	$	1,036,120	$	1,262,818

Contract assets recorded in Prepaid expenses and other current assets (2)	$	24,905	$	26,119

Contract liabilities:
Deferred revenues (current liability) (3)	$	1,803,135	$	1,745,244
Non-current deferred revenues recorded in Other liabilities (3)	15,784		21,194
Total contract liabilities	$	1,818,919	$	1,766,438


(1)	Fees receivable represent an unconditional right of payment from our customers and include both billed and unbilled amounts.


(2)	Contract assets represent recognized revenue for which we do not have an unconditional right to payment as of the balance sheet date because the project may be subject to a progress billing milestone or some other billing restriction.


(3)	Deferred revenues represent amounts (i) for which the Company has received an upfront customer payment or (ii) that pertain to recognized fees receivable. Both situations occur before the completion of our performance obligation(s).

Acquisitions

Divestitures

Adoption of new accounting standards and Accounting standards issued but not yet adopted


•	Existing contracts were not reassessed to determine if they contained leases.


•	Existing leases were not reassessed to determine if their classification should be changed.


•	Initial direct costs for existing leases were not reassessed.


•	Lease components and nonlease components (e.g., common area maintenance charges, etc.) related to a lease arrangement were accounted for as a single lease component for purposes of the recognition and measurement requirements of ASU No. 2016-02.


•	The incremental borrowing rate used for the purpose of measuring each of our lease liabilities was derived by reference to the related lease’s remaining minimum payments and remaining lease term on the date of adopting the new lease standard. We used incremental borrowing rates because we were unable to determine the implicit interest rates in our leases.

Leasing Activities

Lease Accounting under ASU No. 2016-02

Lease Disclosures Under ASU No. 2016-02



Description:	Three Months Ended September 30, 2019			Nine Months Ended September 30, 2019
Operating lease cost (1)	$	35,443		$	106,958
Variable lease cost (2)	3,902			11,517
Sublease income	(10,205		)	(30,767		)
Total lease cost, net (3)	$	29,140		$	87,708

Cash paid for amounts included in the measurement of operating lease liabilities	$	34,294		$	100,172
Cash receipts from sublease arrangements	$	9,000		$	25,131
Right-of-use assets obtained in exchange for new operating lease liabilities	$	38,571		$	67,756

As of September 30, 2019:
Weighted average remaining lease term for operating leases (in years)				10.5
Weighted average discount rate for operating leases				6.9		%


(1)	Included in operating lease cost was $10.8 million and $32.5 million of costs for subleasing activities during the three and nine months ended September 30, 2019, respectively.


(2)	These amounts are primarily variable lease and nonlease costs that were not fixed at the lease commencement date or are dependent on something other than an index or a rate.


(3)	The Company did not capitalize any operating lease costs during the three and nine months ended September 30, 2019.



	Operating			Sublease
	Lease			Cash
Period ending December 31,	Payments			Receipts
2019 (remaining three months)	$	35,125		$	9,344
2020	133,534			40,534
2021	126,602			42,918
2022	121,021			43,587
2023	115,034			44,469
Thereafter	693,901			177,741
Total future minimum operating lease payments and estimated sublease cash receipts (1)	1,225,217			$	358,593
Imputed interest	(368,485		)
Total per the Condensed Consolidated Balance Sheet	$	856,732


(1)	Approximately 84% of the operating lease payments pertain to properties in the United States.



Description:
Accounts payable and accrued liabilities	$	80,170
Operating leases - liabilities	776,562
Total operating lease liabilities per the Condensed Consolidated Balance Sheet	$	856,732

Lease Disclosures Under Prior GAAP

Based on the Company's selected method of adoption for ASU No. 2016-02, the prior GAAP disclosures presented below are required in our Condensed Consolidated Financial Statements.



Year ending December 31,
2019	$	130,991
2020	121,802
2021	118,945
2022	111,117
2023	106,113
Thereafter	689,360
Total minimum lease payments (1)	$	1,278,328

(1) Excludes approximately $372.0 million of sublease income.

Accounting standards effective in 2020

Business and Basis of Presentation (Tables)

9 Months Ended

Sep. 30, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Disaggregation of Revenue by Reportable Segment

Our disaggregated revenue by reportable segment is presented in the tables below for the periods indicated (in thousands).

By Primary Geographic Market (1), (2)

Three Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Primary Geographic Markets
United States and Canada	$	538,112	$	28,153	$	58,615	$	624,880
Europe, Middle East and Africa	196,121		24,497		26,468		247,086
Other International	106,765		13,636		8,135		128,536
Total revenues	$	840,998	$	66,286	$	93,218	$	1,000,502

Three Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Primary Geographic Markets
United States and Canada	$	502,489	$	22,002	$	45,903	$	8,948	$	579,342
Europe, Middle East and Africa	180,124		25,422		26,255		2,645		234,446
Other International	91,575		9,717		6,594		—		107,886
Total revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674

Nine Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Primary Geographic Markets
United States and Canada	$	1,593,806	$	157,756	$	175,208	$	1,926,770
Europe, Middle East and Africa	583,742		67,520		90,350		741,612
Other International	314,879		34,116		24,451		373,446
Total revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828

Nine Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Primary Geographic Markets
United States and Canada	$	1,485,545	$	131,215	$	146,816	$	59,419	$	1,822,995
Europe, Middle East and Africa	551,070		57,163		89,783		38,369		736,385
Other International	271,811		26,103		21,507		7,774		327,195
Total revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575


(1)	Revenue is reported based on where the sale is fulfilled.


(2)	During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

Schedule of Disaggregation of Revenue

Three Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Timing of Revenue Recognition
Transferred over time (2)	$	769,718	$	—	$	77,570	$	847,288
Transferred at a point in time (3)	71,280		66,286		15,648		153,214
Total revenues	$	840,998	$	66,286	$	93,218	$	1,000,502

Three Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Timing of Revenue Recognition
Transferred over time (2)	$	709,496	$	—	$	69,755	$	8,800	$	788,051
Transferred at a point in time (3)	64,692		57,141		8,997		2,793		133,623
Total revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674

Nine Months Ended September 30, 2019



	Research		Conferences		Consulting		Total
Timing of Revenue Recognition
Transferred over time (2)	$	2,276,783	$	—	$	235,641	$	2,512,424
Transferred at a point in time (3)	215,644		259,392		54,368		529,404
Total revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828

Nine Months Ended September 30, 2018



	Research		Conferences		Consulting		Other		Total
Timing of Revenue Recognition
Transferred over time (2)	$	2,119,393	$	—	$	220,838	$	86,667	$	2,426,898
Transferred at a point in time (3)	189,033		214,481		37,268		18,895		459,677
Total revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575


(1)	During 2018, the Company divested all of the non-core businesses that comprised its Other segment and moved a small residual product in the Other segment into the Research business and, as a result, no operating activity has been recorded in the Other segment in 2019.

(2)

(3)

The revenues in this category were recognized in connection with performance obligations that were satisfied at the point in time the contractual deliverables were provided to the customer.

Schedule for Contract with Customer, Asset and Liability

The table below provides information regarding certain of the Company’s balance sheet accounts that pertain to its contracts with customers (in thousands).



	September 30,		December 31,
	2019		2018
Assets:
Fees receivable, gross (1)	$	1,036,120	$	1,262,818

Contract assets recorded in Prepaid expenses and other current assets (2)	$	24,905	$	26,119

Contract liabilities:
Deferred revenues (current liability) (3)	$	1,803,135	$	1,745,244
Non-current deferred revenues recorded in Other liabilities (3)	15,784		21,194
Total contract liabilities	$	1,818,919	$	1,766,438


(1)	Fees receivable represent an unconditional right of payment from our customers and include both billed and unbilled amounts.


(2)	Contract assets represent recognized revenue for which we do not have an unconditional right to payment as of the balance sheet date because the project may be subject to a progress billing milestone or some other billing restriction.

(3)

Deferred revenues represent amounts (i) for which the Company has received an upfront customer payment or (ii) that pertain to recognized fees receivable. Both situations occur before the completion of our performance obligation(s).

Lease costs

The table below presents the Company’s net lease cost and certain other information related to the Company’s leasing activities as of and for the periods indicated (dollars in thousands).



Description:	Three Months Ended September 30, 2019			Nine Months Ended September 30, 2019
Operating lease cost (1)	$	35,443		$	106,958
Variable lease cost (2)	3,902			11,517
Sublease income	(10,205		)	(30,767		)
Total lease cost, net (3)	$	29,140		$	87,708

Cash paid for amounts included in the measurement of operating lease liabilities	$	34,294		$	100,172
Cash receipts from sublease arrangements	$	9,000		$	25,131
Right-of-use assets obtained in exchange for new operating lease liabilities	$	38,571		$	67,756

As of September 30, 2019:
Weighted average remaining lease term for operating leases (in years)				10.5
Weighted average discount rate for operating leases				6.9		%


(1)	Included in operating lease cost was $10.8 million and $32.5 million of costs for subleasing activities during the three and nine months ended September 30, 2019, respectively.


(2)	These amounts are primarily variable lease and nonlease costs that were not fixed at the lease commencement date or are dependent on something other than an index or a rate.


(3)	The Company did not capitalize any operating lease costs during the three and nine months ended September 30, 2019.

Operating lease maturity schedule



	Operating			Sublease
	Lease			Cash
Period ending December 31,	Payments			Receipts
2019 (remaining three months)	$	35,125		$	9,344
2020	133,534			40,534
2021	126,602			42,918
2022	121,021			43,587
2023	115,034			44,469
Thereafter	693,901			177,741
Total future minimum operating lease payments and estimated sublease cash receipts (1)	1,225,217			$	358,593
Imputed interest	(368,485		)
Total per the Condensed Consolidated Balance Sheet	$	856,732


(1)	Approximately 84% of the operating lease payments pertain to properties in the United States.

Supplemental balance sheet information



Description:
Accounts payable and accrued liabilities	$	80,170
Operating leases - liabilities	776,562
Total operating lease liabilities per the Condensed Consolidated Balance Sheet	$	856,732

Schedule of Future Minimum Lease Payments for Capital Leases



Year ending December 31,
2019	$	130,991
2020	121,802
2021	118,945
2022	111,117
2023	106,113
Thereafter	689,360
Total minimum lease payments (1)	$	1,278,328

(1) Excludes approximately $372.0 million of sublease income.

Computation of Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2019

Earnings Per Share [Abstract]

Schedule of basic and diluted (loss) earnings per share calculations

The table below sets forth the calculation of basic and diluted income per share for the periods indicated (in thousands, except per share data).



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2019		2018		2019		2018
Numerator:
Net income used for calculating basic and diluted income per common share	$	41,388	$	11,753	$	165,589	$	38,436

Denominator:
Weighted average common shares used in the calculation of basic income per share	89,846		90,854		89,947		90,969
Common stock equivalents associated with stock-based compensation plans (1)	1,041		1,294		1,142		1,275
Shares used in the calculation of diluted income per share	90,887		92,148		91,089		92,244

Basic income per share	$	0.46	$	0.13	$	1.84	$	0.42
Diluted income per share	$	0.46	$	0.13	$	1.82	$	0.42

(1)

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2019

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of stock-based compensation expense by award type

The Company recognized the following stock-based compensation expense by award type and expense category line item during the periods indicated (in millions):



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
Award type	2019		2018		2019		2018
Stock appreciation rights	$	1.0	$	0.8	$	5.8	$	5.6
Restricted stock units	11.8		9.8		51.5		49.9
Common stock equivalents	0.2		0.1		0.6		0.5
Total (1)	$	13.0	$	10.7	$	57.9	$	56.0



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
Expense category line item	2019		2018		2019		2018
Cost of services and product development	$	6.2	$	4.7	$	23.7	$	22.8
Selling, general and administrative	6.7		5.7		33.8		31.4
Acquisition and integration charges (2)	0.1		0.3		0.4		1.8
Total (1)	$	13.0	$	10.7	$	57.9	$	56.0

(2) Includes charges related to an acquisition and the related integration process.

Schedule of stock-based compensation expense by expense category



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
Expense category line item	2019		2018		2019		2018
Cost of services and product development	$	6.2	$	4.7	$	23.7	$	22.8
Selling, general and administrative	6.7		5.7		33.8		31.4
Acquisition and integration charges (2)	0.1		0.3		0.4		1.8
Total (1)	$	13.0	$	10.7	$	57.9	$	56.0

(2) Includes charges related to an acquisition and the related integration process.

Schedule of fair value assumptions of SARs

The fair value of a SARs award is determined on the date of grant using the Black-Scholes-Merton valuation model with the following weighted average assumptions:



	Nine Months Ended
	September 30,
	2019		2018
Expected dividend yield (1)	—	%	—	%
Expected stock price volatility (2)	21	%	21	%
Risk-free interest rate (3)	2.5	%	2.5	%
Expected life in years (4)	4.6		4.5


(1)	The expected dividend yield assumption was based on both the Company's historical and anticipated dividend payouts. Historically, the Company has not paid cash dividends on its Common Stock.


(2)	The determination of expected stock price volatility was based on both historical Common Stock prices and implied volatility from publicly traded options in the Common Stock.


(3)	The risk-free interest rate was based on the yield of a U.S. Treasury security with a maturity similar to the expected life of the award.


(4)	The expected life represents the Company’s estimate of the weighted average period of time the SARs are expected to be outstanding (that is, the period between the service inception date and the expected exercise date).

Stock appreciation rights

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of summary of the changes in SARS, RSUs, and CSEs outstanding

The table below summarizes changes in SARs outstanding during the nine months ended September 30, 2019.



	Stock Appreciation Rights ("SARs") (in millions)		Per Share Weighted Average Exercise Price		Per Share Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term (Years)
Outstanding at December 31, 2018	1.2		$	89.45	$	19.88	4.33
Granted	0.3		143.23		32.62		6.36
Forfeited	(0.1	)	118.31		26.52		n/a
Exercised	(0.1	)	70.54		16.64		n/a
Outstanding at September 30, 2019 (1) (2)	1.3		$	100.54	$	22.43	4.18
Vested and exercisable at September 30, 2019 (2)	0.7		$	83.36	$	18.46	3.11

n/a = not applicable

(1) As of September 30, 2019, 0.6 million of the total SARs outstanding were unvested. The Company expects that substantially all of those unvested awards will vest in future periods.

(2) As of September 30, 2019, the total SARs outstanding had an intrinsic value of $56.9 million. On such date, SARs vested and exercisable had an intrinsic value of $42.1 million.

Restricted stock units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of summary of the changes in SARS, RSUs, and CSEs outstanding

The table below summarizes the changes in RSUs outstanding during the nine months ended September 30, 2019.



	Restricted Stock Units ("RSUs") (in millions)		Per Share Weighted Average Grant Date Fair Value
Outstanding at December 31, 2018	1.4		$	101.75
Granted (1)	0.5		139.84
Vested and released	(0.5	)	97.13
Forfeited	(0.1	)	115.15
Outstanding at September 30, 2019 (2) (3)	1.3		$	118.94

(1)


(2)	The Company expects that substantially all of the RSUs outstanding will vest in future periods.

(3)

As of September 30, 2019, the weighted-average remaining contractual term of the RSUs outstanding was approximately 1.3 years.

Common stock equivalents

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of summary of the changes in SARS, RSUs, and CSEs outstanding

The table below summarizes the changes in CSEs outstanding during the nine months ended September 30, 2019.



	Common Stock Equivalents ("CSEs")		Per Share Weighted Average Grant Date Fair Value
Outstanding at December 31, 2018	109,780		$	24.96
Granted	3,410		152.58
Converted to shares of Common Stock upon grant	(2,199	)	146.28
Outstanding at September 30, 2019	110,991		$	26.48

Segment Information (Tables)

9 Months Ended

Sep. 30, 2019

Segment Reporting [Abstract]

Schedule of segment reporting information, by segment

The tables below present information about the Company’s reportable segments for the periods indicated (in thousands) (1).



Three Months Ended September 30, 2019	Research		Conferences		Consulting		Consolidated
Revenues	$	840,998	$	66,286	$	93,218	$	1,000,502
Gross contribution	582,502		27,465		26,538		636,505
Corporate and other expenses							(567,358		)
Operating income							$	69,147



Three Months Ended September 30, 2018	Research		Conferences		Consulting		Other		Consolidated
Revenues	$	774,188	$	57,141	$	78,752	$	11,593	$	921,674
Gross contribution	534,911		25,047		18,419		6,927		585,304
Corporate and other expenses									(532,580		)
Operating income									$	52,724



Nine Months Ended September 30, 2019	Research		Conferences		Consulting		Consolidated
Revenues	$	2,492,427	$	259,392	$	290,009	$	3,041,828
Gross contribution	1,729,967		126,910		89,493		1,946,370
Corporate and other expenses							(1,712,422		)
Operating income							$	233,948



Nine Months Ended September 30, 2018	Research		Conferences		Consulting		Other		Consolidated
Revenues	$	2,308,426	$	214,481	$	258,106	$	105,562	$	2,886,575
Gross contribution	1,599,277		104,698		76,236		65,075		1,845,286
Corporate and other expenses									(1,715,177		)
Operating income									$	130,109

Schedule of reconciliation of segment gross contribution to net income (loss)

The table below provides a reconciliation of total segment gross contribution to net income for the periods indicated (in thousands).



	Three Months Ended					Nine Months Ended
	September 30,					September 30,
	2019		2018			2019			2018
Total segment gross contribution	$	636,505	$	585,304		$	1,946,370		$	1,845,286
Costs and expenses:
Cost of services and product development - unallocated (1)	1,059		(258		)	4,242			19,669
Selling, general and administrative	512,159		447,537			1,545,905			1,396,085
Depreciation and amortization	52,398		68,187			158,119			203,081
Acquisition and integration charges	1,742		17,114			4,156			96,342
Operating income	69,147		52,724			233,948			130,109
Interest expense and other, net	16,049		27,811			66,716			98,454
Gain (loss) from divested operations	—		13,040			(2,075		)	38,500
Provision (benefit) for income taxes	11,710		26,200			(432		)	31,719
Net income	$	41,388	$	11,753		$	165,589		$	38,436

(1)

Goodwill and Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of changes to the carrying amount of goodwill by reporting unit

The table below presents changes to the carrying amount of goodwill by segment during the nine months ended September 30, 2019 (in thousands).



	Research		Conferences		Consulting			Total
Balance at December 31, 2018 (1)	$	2,638,418	$	187,654	$	97,064		$	2,923,136
Foreign currency translation impact	16,745		24		(198		)	16,571
Balance at September 30, 2019	$	2,655,163	$	187,678	$	96,866		$	2,939,707


(1)	The Company does not have any accumulated goodwill impairment losses.

Schedule of amortizable intangible assets

The tables below present reconciliations of the carrying amounts of the Company's finite-lived intangible assets as of the dates indicated (in thousands).



September 30, 2019	Customer Relationships			Software			Content			Other			Total
Gross cost at December 31, 2018	$	1,131,656		$	110,701		$	98,842		$	51,662		$	1,392,861
Intangible assets fully amortized	—			—			(85,900		)	(18,680		)	(104,580		)
Foreign currency translation impact	(9,810		)	(303		)	(2		)	(106		)	(10,221		)
Gross cost	1,121,846			110,398			12,940			32,876			1,278,060
Accumulated amortization (1)	(255,139		)	(55,609		)	(9,973		)	(21,026		)	(341,747		)
Balance at September 30, 2019	$	866,707		$	54,789		$	2,967		$	11,850		$	936,313



December 31, 2018	Customer Relationships			Software			Content			Other			Total
Gross cost	$	1,131,656		$	110,701		$	98,842		$	51,662		$	1,392,861
Accumulated amortization (1)	(184,918		)	(38,901		)	(92,717		)	(33,760		)	(350,296		)
Balance at December 31, 2018	$	946,738		$	71,800		$	6,125		$	17,902		$	1,042,565

Schedule of estimated future amortization expense by year

The estimated future amortization expense by year for finite-lived intangible assets is as follows (in thousands):



2019 (remaining three months)	$	31,812
2020	122,864
2021	102,493
2022	92,989
2023	92,989
Thereafter	493,166
	$	936,313

Debt (Tables)

9 Months Ended

Sep. 30, 2019

Debt Disclosure [Abstract]

Schedule of debt

The table below summarizes the Company’s total outstanding borrowings as of the dates indicated (in thousands).



	September 30,			December 31,
Description:	2019			2018
2016 Credit Agreement - Term loan A facility (1)	$	1,280,813		$	1,355,062
2016 Credit Agreement - Revolving credit facility (1), (2)	120,000			155,000
Senior Notes (3)	800,000			800,000
Other (4)	6,667			2,030
Principal amount outstanding (5)	2,207,480			2,312,092
Less: deferred financing fees (6)	(25,540		)	(30,405		)
Net balance sheet carrying amount	$	2,181,940		$	2,281,687


(1)	The contractual annualized interest rate as of September 30, 2019 on the Term loan A facility and the revolving credit facility was 3.54%, which consisted of a floating eurodollar base rate of 2.04% plus a margin of 1.50%. However, the Company has interest rate swap contracts that effectively convert the floating eurodollar base rates on amounts outstanding to a fixed base rate.


(2)	The Company had approximately $1.1 billion of available borrowing capacity on the revolver (not including the expansion feature) as of September 30, 2019.


(3)	Consists of $800.0 million principal amount of Senior Notes outstanding. The Senior Notes pay a fixed rate of 5.125% and mature on April 1, 2025.

(4)


(5)	The weighted average annual effective rates on the Company's total debt outstanding for the three and nine months ended September 30, 2019, including the effects of its interest rate swaps discussed below, was 4.00% and 4.01%, respectively.


(6)	Deferred financing fees are being amortized to Interest expense, net over the term of the related debt obligation.

Equity (Tables)

9 Months Ended

Sep. 30, 2019

Stockholders' Equity Note [Abstract]

Schedule of share repurchase activity

The Company’s share repurchase activity for the periods indicated is presented in the table below.



	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2019		2018		2019		2018
Number of shares repurchased (1)	705,800		51,298		929,311		815,001
Cash paid for repurchased shares (in thousands) (2)	$	94,878	$	8,129	$	141,436	$	104,400

(2) The cash paid for repurchased shares during the nine months ended September 30, 2019 included open market purchases with trade dates in December 2018 that settled in January 2019.

Schedule of Stockholders Equity

The tables below provide a reconciliation of changes in the Company's Stockholders' Equity for the periods indicated (in thousands).

Three Months Ended September 30, 2019



	Common Stock		Additional Paid-In Capital		Accumulated Other Comprehensive Loss, Net			Accumulated Earnings		Treasury Stock			Total
Balance at June 30, 2019	$	82	$	1,868,878	$	(73,479	)	$	1,879,633	$	(2,711,312	)	$	963,802
Net income	—		—		—			41,388		—			41,388
Other comprehensive loss	—		—		(7,785		)	—		—			(7,785		)
Issuances under stock plans	—		3,538		—			—		633			4,171
Common share repurchases	—		—		—			—		(94,873		)	(94,873		)
Stock-based compensation expense	—		12,954		—			—		—			12,954
Balance at September 30, 2019	$	82	$	1,885,370	$	(81,264	)	$	1,921,021	$	(2,805,552	)	$	919,657

Three Months Ended September 30, 2018



	Common Stock		Additional Paid-In Capital		Accumulated Other Comprehensive Loss, Net			Accumulated Earnings		Treasury Stock			Total
Balance at June 30, 2018	$	82	$	1,798,075	$	(24,051	)	$	1,659,658	$	(2,512,332	)	$	921,432
Net income	—		—		—			11,753		—			11,753
Other comprehensive income	—		—		1,367			—		—			1,367
Issuances under stock plans	—		1,752		—			—		1,711			3,463
Common share repurchases	—		—		—			—		(7,186		)	(7,186		)
Stock-based compensation expense	—		10,718		—			—		—			10,718
Balance at September 30, 2018	$	82	$	1,810,545	$	(22,684	)	$	1,671,412	$	(2,517,807	)	$	941,548

Nine Months Ended September 30, 2019



	Common Stock		Additional Paid-In Capital		Accumulated Other Comprehensive Loss, Net			Accumulated Earnings		Treasury Stock			Total
Balance at December 31, 2018	$	82	$	1,823,710	$	(39,867	)	$	1,755,432	$	(2,688,600	)	$	850,757
Net income	—		—		—			165,589		—			165,589
Other comprehensive loss	—		—		(41,397		)	—		—			(41,397		)
Issuances under stock plans	—		3,767		—			—		9,481			13,248
Common share repurchases	—		—		—			—		(126,433		)	(126,433		)
Stock-based compensation expense	—		57,893		—			—		—			57,893
Balance at September 30, 2019	$	82	$	1,885,370	$	(81,264	)	$	1,921,021	$	(2,805,552	)	$	919,657

Nine Months Ended September 30, 2018



	Common Stock		Additional Paid-In Capital			Accumulated Other Comprehensive Income (Loss), Net			Accumulated Earnings			Treasury Stock			Total
Balance at December 31, 2017	$	82	$	1,761,383		$	1,508		$	1,647,284		$	(2,426,792	)	$	983,465
Adoption of ASU No. 2018-02 (1)	—		—			591			(591		)	—			—
Adoption of ASU No. 2016-16 (2)	—		—			—			(13,717		)	—			(13,717		)
Net income	—		—			—			38,436			—			38,436
Other comprehensive loss	—		—			(24,783		)	—			—			(24,783		)
Issuances under stock plans	—		(6,856		)	—			—			13,385			6,529
Common share repurchases	—		—			—			—			(104,400		)	(104,400		)
Stock-based compensation expense	—		56,018			—			—			—			56,018
Balance at September 30, 2018	$	82	$	1,810,545		$	(22,684	)	$	1,671,412		$	(2,517,807	)	$	941,548


(1)	On April 1, 2018, the Company early adopted ASU No. 2018-02, "Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income" ("ASU No. 2018-02"), which resulted in a reclassification of $0.6 million of stranded tax amounts related to the U.S. Tax Cuts and Jobs Act of 2017 from Accumulated other comprehensive income (loss), net to Accumulated earnings.

(2)

Schedule of the changes in Accumulated Other Comprehensive (Loss) Income by component (net of tax)

The tables below provide information about the changes in AOCI/L by component and the related amounts reclassified out of AOCI/L to income during the periods indicated (net of tax, in thousands) (1).

Three Months Ended September 30, 2019



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – June 30, 2019	$	(46,990	)	$	(5,655	)	$	(20,834	)	$	(73,479	)
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	(10,285		)	—			3,553			(6,731		)
Reclassifications from AOCI/L to income (2), (3)	(1,094		)	41			—			(1,054		)
Other comprehensive income (loss) for the period	(11,379		)	41			3,553			(7,785		)
Balance – September 30, 2019	$	(58,369	)	$	(5,614	)	$	(17,281	)	$	(81,264	)

Three Months Ended September 30, 2018



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – June 30, 2018	$	16,281		$	(5,750	)	$	(34,582	)	$	(24,051	)
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	969			—			814			1,783
Reclassifications from AOCI/L to income (2), (3), (4)	(619		)	53			150			(416		)
Other comprehensive income (loss) for the period	350			53			964			1,367
Balance – September 30, 2018	$	16,631		$	(5,697	)	$	(33,618	)	$	(22,684	)

Nine Months Ended September 30, 2019



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – December 31, 2018	$	(7,770	)	$	(5,738	)	$	(26,359	)	$	(39,867	)
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	(46,224		)	—			9,078			(37,146		)
Reclassifications from AOCI/L to income (2), (3)	(4,375		)	124			—			(4,251		)
Other comprehensive income (loss) for the period	(50,599		)	124			9,078			(41,397		)
Balance – September 30, 2019	$	(58,369	)	$	(5,614	)	$	(17,281	)	$	(81,264	)

Nine Months Ended September 30, 2018



	Interest Rate Swaps			Defined Benefit Pension Plans			Foreign Currency Translation Adjustments			Total
Balance – December 31, 2017	$	2,483		$	(5,861	)	$	4,886		1,508
Adoption of ASU No. 2018-02 (5)	591			—			—			591
Other comprehensive income (loss) activity during the period:
Change in AOCI/L before reclassifications to income	13,748			—			21,656			35,404
Reclassifications from AOCI/L to income (2), (3), (4)	(191		)	164			(60,160		)	(60,187	)
Other comprehensive income (loss) for the period	13,557			164			(38,504		)	(24,783	)
Balance – September 30, 2018	$	16,631		$	(5,697	)	$	(33,618	)	(22,684	)


(1)	Amounts in parentheses represent debits (deferred losses).


(2)	The reclassifications related to interest rate swaps (cash flow hedges) were recorded in Interest expense, net of tax effect. See Note 6 – Debt and Note 9 – Derivatives and Hedging for information regarding the cash flow hedges.


(3)	The reclassifications related to defined benefit pension plans were primarily recorded in Selling, general and administrative expense, net of tax effect. See Note 11 – Employee Benefits for information regarding the Company’s defined benefit pension plans.


(4)	The reclassifications related to foreign currency translation adjustments in 2018 were recorded in Gain (loss) from divested operations. See Note 1 – Business and Basis of Presentation for information regarding our divestitures in 2018.

(5)

Derivatives and Hedging (Tables)

9 Months Ended

Sep. 30, 2019

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of information regarding outstanding derivative contracts

The tables below provide information regarding the Company’s outstanding derivative contracts as of the dates indicated (in thousands, except for number of contracts).



September 30, 2019
Derivative Contract Type	Number of Contracts	Notional Amounts		Fair Value Asset (Liability), Net (3)			Balance Sheet Line Item	Unrealized Loss Recorded in AOCI/L
Interest rate swaps (1)	4	$	1,400,000	$	(80,233	)	Other liabilities	$	(58,369	)
Foreign currency forwards (2)	40	203,351		(220		)	Accrued liabilities	—
Total	44	$	1,603,351	$	(80,453	)		$	(58,369	)



December 31, 2018
Derivative Contract Type	Number of Contracts	Notional Amounts		Fair Value Asset (Liability), Net (3)			Balance Sheet Line Item	Unrealized Loss Recorded in AOCI/L
Interest rate swaps (1)	7	$	2,100,000	$	(10,681	)	Other liabilities	$	(7,770	)
Foreign currency forwards (2)	135	927,375		(1,942		)	Accrued liabilities	—
Total	142	$	3,027,375	$	(12,623	)		$	(7,770	)


(1)	The interest rate swaps have been designated and are accounted for as cash flow hedges of the forecasted interest payments on borrowings. As a result, changes in the fair values of the swaps are deferred and recorded in AOCI/L, net of tax effect. Note 6 — Debt provides additional information.

(2)


(3)	See Note 10 — Fair Value Disclosures for the determination of the fair values of these instruments.

Schedule of amounts recognized in statement of operations

The table below provides information regarding amounts recognized in the accompanying Condensed Consolidated Statements of Operations for derivative contracts for the periods indicated (in thousands).



	Three Months Ended						Nine Months Ended
	September 30,						September 30,
Amount recorded in:	2019			2018			2019			2018
Interest (income) expense, net (1)	$	(1,504	)	$	(851	)	$	(6,015	)	$	(262	)
Other expense, net (2)	4,367			1,140			5,064			2,815
Total expense (income), net	$	2,863		$	289		$	(951	)	$	2,553


(1)	Consists of interest (income) expense from interest rate swap contracts.

(2)

Consists of net realized and unrealized gains and losses on foreign currency forward contracts.

Fair Value Disclosures (Tables)

9 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Schedule of assets and liabilities that are remeasured to fair value

The table below presents the fair value of certain financial assets and liabilities (in thousands).



Description:	September 30, 2019		December 31, 2018
Assets:
Values based on Level 1 inputs:
Deferred compensation plan assets (1)	$	8,985	$	8,956
Total Level 1 inputs	8,985		8,956
Values based on Level 2 inputs:
Deferred compensation plan assets (1)	61,491		57,690
Foreign currency forward contracts (2)	65		1,318
Total Level 2 inputs	61,556		59,008
Total Assets	$	70,541	$	67,964
Liabilities:
Values based on Level 2 inputs:
Deferred compensation plan liabilities (1)	$	74,308	$	68,570
Foreign currency forward contracts (2)	285		3,260
Interest rate swap contracts (3)	80,233		10,681
Senior Notes due 2025 (4)	838,584		776,160
Total Level 2 inputs	993,410		858,671
Total Liabilities	$	993,410	$	858,671

(1)


(2)	The Company enters into foreign currency forward exchange contracts to hedge the effects of adverse fluctuations in foreign currency exchange rates (see Note 9 — Derivatives and Hedging). Valuation of these contracts is based on observable foreign currency exchange rates in active markets, which the Company considers to be a Level 2 input.

(3)

(4)

Business and Basis of Presentation - Narrative (Details)	9 Months Ended
	Sep. 30, 2019 segment country company
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of organizations Company serves \| company	15,000
Number of countries in which entity operates \| country	100
Number of reportable segments \| segment	3

Business and Basis of Presentation - Disaggregation of Revenue by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues	$ 1,000,502	$ 921,674	$ 3,041,828	$ 2,886,575
Research
Disaggregation of Revenue [Line Items]
Total revenues	840,998	774,188	2,492,427	2,308,426
Conferences
Disaggregation of Revenue [Line Items]
Total revenues	66,286	57,141	259,392	214,481
Consulting
Disaggregation of Revenue [Line Items]
Total revenues	93,218	78,752	290,009	258,106
Other
Disaggregation of Revenue [Line Items]
Total revenues		11,593		105,562
United States and Canada
Disaggregation of Revenue [Line Items]
Total revenues	624,880	579,342	1,926,770	1,822,995
United States and Canada \| Research
Disaggregation of Revenue [Line Items]
Total revenues	538,112	502,489	1,593,806	1,485,545
United States and Canada \| Conferences
Disaggregation of Revenue [Line Items]
Total revenues	28,153	22,002	157,756	131,215
United States and Canada \| Consulting
Disaggregation of Revenue [Line Items]
Total revenues	58,615	45,903	175,208	146,816
United States and Canada \| Other
Disaggregation of Revenue [Line Items]
Total revenues		8,948		59,419
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Total revenues	247,086	234,446	741,612	736,385
Europe, Middle East and Africa \| Research
Disaggregation of Revenue [Line Items]
Total revenues	196,121	180,124	583,742	551,070
Europe, Middle East and Africa \| Conferences
Disaggregation of Revenue [Line Items]
Total revenues	24,497	25,422	67,520	57,163
Europe, Middle East and Africa \| Consulting
Disaggregation of Revenue [Line Items]
Total revenues	26,468	26,255	90,350	89,783
Europe, Middle East and Africa \| Other
Disaggregation of Revenue [Line Items]
Total revenues		2,645		38,369
Other International
Disaggregation of Revenue [Line Items]
Total revenues	128,536	107,886	373,446	327,195
Other International \| Research
Disaggregation of Revenue [Line Items]
Total revenues	106,765	91,575	314,879	271,811
Other International \| Conferences
Disaggregation of Revenue [Line Items]
Total revenues	13,636	9,717	34,116	26,103
Other International \| Consulting
Disaggregation of Revenue [Line Items]
Total revenues	$ 8,135	6,594	$ 24,451	21,507
Other International \| Other
Disaggregation of Revenue [Line Items]
Total revenues		$ 0		$ 7,774

Business and Basis of Presentation - Timing Of Revenue Recognition Liabilities per Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues	$ 1,000,502	$ 921,674	$ 3,041,828	$ 2,886,575
Transferred over time
Disaggregation of Revenue [Line Items]
Total revenues	847,288	788,051	2,512,424	2,426,898
Transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues	153,214	133,623	529,404	459,677
Research
Disaggregation of Revenue [Line Items]
Total revenues	840,998	774,188	2,492,427	2,308,426
Research \| Transferred over time
Disaggregation of Revenue [Line Items]
Total revenues	769,718	709,496	2,276,783	2,119,393
Research \| Transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues	71,280	64,692	215,644	189,033
Conferences
Disaggregation of Revenue [Line Items]
Total revenues	66,286	57,141	259,392	214,481
Conferences \| Transferred over time
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Conferences \| Transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues	66,286	57,141	259,392	214,481
Consulting
Disaggregation of Revenue [Line Items]
Total revenues	93,218	78,752	290,009	258,106
Consulting \| Transferred over time
Disaggregation of Revenue [Line Items]
Total revenues	77,570	69,755	235,641	220,838
Consulting \| Transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues	$ 15,648	8,997	$ 54,368	37,268
Other
Disaggregation of Revenue [Line Items]
Total revenues		11,593		105,562
Other \| Transferred over time
Disaggregation of Revenue [Line Items]
Total revenues		8,800		86,667
Other \| Transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues		$ 2,793		$ 18,895

Business and Basis of Presentation - Revenue Remaining Performance Obligation (Details) $ in Millions	Sep. 30, 2019 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 514.2
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	1,592.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	750.1
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation	$ 2,900.0

Business and Basis of Presentation - Schedule of Contract with Customer, Asset and Liability (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets:
Fees receivable, gross	$ 1,036,120	$ 1,262,818
Contract assets recorded in Prepaid expenses and other current assets	24,905	26,119
Contract liabilities:
Deferred revenues (current liability)	1,803,135	1,745,244
Non-current deferred revenues recorded in Other liabilities	15,784	21,194
Total contract liabilities	$ 1,818,919	$ 1,766,438

Business and Basis of Presentation - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($) business	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue recognized previously attributable to deferred revenues	$ 675,200,000	$ 642,000,000.0	$ 1,312,300,000	$ 1,164,200,000
Acquisition and integration charges	1,742,000	17,114,000	4,156,000	96,342,000
Business exit costs				51,400,000
Deferred consideration from pre-2018 acquisitions			2,295,000	$ 15,855,000
Number of businesses sold \| business				3
Disposal group, revenue		8,600,000		$ 97,000,000.0
Disposal group, pre-tax income		4,900,000		60,100,000
Cash received from divestitures			0	520,709,000
Gain (loss) from divested operations	0	13,040,000	(2,075,000)	38,500,000
Unrealized appreciation			9,120,000	0
Cash and cash equivalents and restricted cash, beginning of period	306,727,000	$ 213,292,000	306,727,000	$ 213,292,000		$ 158,663,000	$ 567,058,000
Cash and cash equivalents	306,727,000		306,727,000			156,368,000
Restricted cash						2,300,000
Operating leases - right-of-use assets	652,273,000		652,273,000		$ 651,900,000
Lease liabilities	856,732,000		856,732,000		851,300,000
Total Assets	6,737,344,000		6,737,344,000			6,201,474,000
Total Liabilities	$ 5,817,687,000		$ 5,817,687,000			$ 5,350,717,000
Renewal term	5 years		5 years
Option to terminate, term			1 year
ASU 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total Assets					638,700,000
Total Liabilities					$ 638,700,000
Other income (expense)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unrealized appreciation	$ 9,100,000		$ 9,100,000
Prepaid expenses and other current assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Minority equity investment fair value	$ 14,100,000		$ 14,100,000

Business and Basis of Presentation - Net Lease Costs (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Operating lease cost	$ 35,443	$ 106,958
Variable lease cost	3,902	11,517
Sublease income	(10,205)	(30,767)
Total lease cost, net	29,140	87,708
Cash paid for amounts included in the measurement of operating lease liabilities	34,294	100,172
Cash receipts from sublease arrangements	9,000	25,131
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 38,571	$ 67,756
Weighted average remaining lease term for operating leases (in years)	10 years 6 months	10 years 6 months
Weighted average discount rate for operating leases	6.90%	6.90%
Cost for subleasing activities	$ 10,800	$ 32,500

Business and Basis of Presentation - Lease Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
Operating Lease Payments
2019 (remaining three months)	$ 35,125
2020	133,534
2021	126,602
2022	121,021
2023	115,034
Thereafter	693,901
Total future minimum operating lease payments and estimated sublease cash receipts	1,225,217
Imputed interest	(368,485)
Total per the Condensed Consolidated Balance Sheet	856,732	$ 851,300
Sublease Cash Receipts
2019 (remaining three months)	9,344
2020	40,534
2021	42,918
2022	43,587
2023	44,469
Thereafter	177,741
Total future minimum operating lease payments and estimated sublease cash receipts (1)	$ 358,593
United States
Lessee, Lease, Description [Line Items]
Percentage of lease payments	84.00%

Business and Basis of Presentation - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts payable and accrued liabilities	$ 80,170
Operating leases - liabilities	776,562
Total operating lease liabilities per the Condensed Consolidated Balance Sheet	856,732	$ 851,300
Leases not yet commenced	$ 146,600
Leases not yet commenced, term	10 years

Business and Basis of Presentation - Leases Under Topic 840 (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
2019	$ 130,991
2020	121,802
2021	118,945
2022	111,117
2023	106,113
Thereafter	689,360
Total minimum lease payments	1,278,328
Sublease income	$ 372,000

Computation of Earnings Per Share - Calculations Of Basic And Diluted (Loss) Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator:
Net income used for calculating basic and diluted income per common share	$ 41,388	$ 11,753	$ 165,589	$ 38,436
Denominator:
Weighted average number of common shares used in the calculation of basic (loss) income per share (in shares)	89,846	90,854	89,947	90,969
Common stock equivalents associated with stock-based compensation plans (in shares)	1,041	1,294	1,142	1,275
Shares used in the calculation of diluted income per share (in shares)	90,887	92,148	91,089	92,244
Basic income per share (in dollars per share)	$ 0.46	$ 0.13	$ 1.84	$ 0.42
Diluted income per share (in dollars per share)	$ 0.46	$ 0.13	$ 1.82	$ 0.42

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Computation of Earnings Per Share - Additional information (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of (loss) income per share (in shares)	0.3	0.2	0.2	0.2

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	4.4
Common stock par value (in dollars per share)	$ 0.0005		$ 0.0005
Total share-based compensation cost not yet recognized	$ 100,000,000.0
Total compensation cost not yet recognized, period for recognition	2 years 6 months
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan, stock purchases as percentage of employee compensation maximum	10.00%
Maximum share value authorized for purchase under employee stock purchase plan	$ 23,750
Exercisable price percentage of closing price of another class of stock	95.00%
Maximum number of shares that may be purchased by eligible participants (in shares)	0.6
Proceeds from stock plans	$ 13,200,000	$ 11,100,000

Stock-Based Compensation - Stock-based Compensation Expense by Award Type and Expense Category (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	$ 13.0	$ 10.7	$ 57.9	$ 56.0
Cost of services and product development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	6.2	4.7	23.7	22.8
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	6.7	5.7	33.8	31.4
Acquisition and integration charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	0.1	0.3	0.4	1.8
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	1.0	0.8	5.8	5.6
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	11.8	9.8	51.5	49.9
Common stock equivalents
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	0.2	0.1	0.6	0.5
Retirement eligible employees equity award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense (credit)	$ 0.4	$ (0.3)	$ 21.8	$ 19.6

Stock-Based Compensation - Summary Of Changes In SARs Outstanding (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, period for recognition	2 years 6 months
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Award expiration period from date of grant	7 years
Total compensation cost not yet recognized, period for recognition	4 years
SARs [Roll Forward]
Outstanding beginning balance (in shares)	1.2
Granted (in shares)	0.3
Forfeited (in shares)	(0.1)
Exercised (in shares)	(0.1)
Outstanding ending balance (in shares)	1.3	1.2
Vested and exercisable at ending balance (in shares)	0.7
Per Share Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning balance (in dollars per share)	$ 89.45
Granted (in dollars per share)	143.23
Forfeited (in dollars per share)	118.31
Exercised (in dollars per share)	70.54
Outstanding at ending balance (in dollars per share)	100.54	$ 89.45
Vested and exercisable at ending balance (in dollars per share)	83.36
Per Share Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding beginning balance (in dollars per share)	19.88
Granted (in dollars per share)	32.62
Forfeited (in dollars per share)	26.52
Exercised (in dollars per share)	16.64
Outstanding ending balance (in dollars per share)	22.43	$ 19.88
Vested and exercisable ending balance (in dollars per share)	$ 18.46
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Remaining Contractual Term [Abstract]
Outstanding weighted average remaining contractual term	4 years 2 months 4 days	4 years 3 months 29 days
Granted	6 years 4 months 9 days
Vested and exercisable at ending balance	3 years 1 month 9 days
Aggregate Intrinsic value of outstanding shares	$ 56.9
Aggregate intrinsic value of shares vested and exercisable	$ 42.1
Unvested \| Stock appreciation rights
SARs [Roll Forward]
Outstanding ending balance (in shares)	0.6

Stock-Based Compensation - Weighted Average Assumptions Used To Determine Fair Value Of SARs Grants On Date Of Grant Using Black-Scholes (Details) - Stock appreciation rights	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected dividend yield	0.00%	0.00%
Expected stock price volatility	21.00%	21.00%
Risk-free interest rate	2.50%	2.50%
Expected life in years	4 years 7 months 6 days	4 years 6 months

Stock-Based Compensation - Summary Of Changes In RSUs Outstanding (Details) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Right to receive, shares	1
Award vesting period	4 years
Restricted Stock Units (RSUs) [Roll Forward]
Outstanding beginning balance (in shares)	1,400,000	1,400,000
Granted (in shares)	500,000
Vested and released (in shares)	(500,000)
Forfeited (in shares)	(100,000)
Outstanding ending balance (in shares)	1,300,000
Per Share Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding beginning balance (in dollars per share)	$ 101.75	$ 101.75
Granted (in dollars per share)	139.84
Vested and released (in dollars per share)	97.13
Forfeited (in dollars per share)	115.15
Outstanding ending balance (in dollars per share)	$ 118.94
Weighted average remaining contractual terms	1 year 3 months 18 days
Restricted stock units \| Executive officer
Restricted Stock Units (RSUs) [Roll Forward]
Granted (in shares)	200,000
Restricted stock units \| Executive officer \| Minimum \| Target amount
Per Share Weighted Average Grant Date Fair Value [Roll Forward]
Percentage of shares authorized for grant	0.00%
Restricted stock units \| Executive officer \| Maximum \| Target amount
Per Share Weighted Average Grant Date Fair Value [Roll Forward]
Percentage of shares authorized for grant	200.00%
Restricted stock units \| Non executive
Restricted Stock Units (RSUs) [Roll Forward]
Granted (in shares)	300,000
Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Forecast \| Restricted stock units
Restricted Stock Units (RSUs) [Roll Forward]
Granted (in shares)		100,000

Stock-Based Compensation - Summary Of Changes In CSEs Outstanding (Details) - Common stock equivalents	9 Months Ended
	Sep. 30, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Right to receive, shares	1
Base fee percentage (up to)	50.00%
Common Stock Equivalents (CSEs) [Roll Forward]
Outstanding beginning balance (in shares)	109,780
Granted (in shares)	3,410
Converted to shares of Common Stock upon grant (in shares)	(2,199)
Outstanding ending balance (in shares)	110,991
Per Share Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding beginning balance (in dollars per share) \| $ / shares	$ 24.96
Granted (in dollars per share) \| $ / shares	152.58
Converted to shares of Common Stock upon grant (in dollars per share) \| $ / shares	146.28
Outstanding ending balance (in dollars per share) \| $ / shares	$ 26.48

Segment Information - Information About Reportable Segments (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) segment	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment			3
Operating income	$ 69,147,000	$ 52,724,000	$ 233,948,000	$ 130,109,000
Intersegment revenues
Segment Reporting Information [Line Items]
Revenues	0	0	0		$ 0
Reportable segments
Segment Reporting Information [Line Items]
Revenues	1,000,502,000	921,674,000	3,041,828,000	2,886,575,000
Operating income	636,505,000	585,304,000	1,946,370,000	1,845,286,000
Corporate and other expenses
Segment Reporting Information [Line Items]
Operating income	(567,358,000)	(532,580,000)	(1,712,422,000)	(1,715,177,000)
Research \| Reportable segments
Segment Reporting Information [Line Items]
Revenues	840,998,000	774,188,000	2,492,427,000	2,308,426,000
Operating income	582,502,000	534,911,000	1,729,967,000	1,599,277,000
Conferences \| Reportable segments
Segment Reporting Information [Line Items]
Revenues	66,286,000	57,141,000	259,392,000	214,481,000
Operating income	27,465,000	25,047,000	126,910,000	104,698,000
Consulting \| Reportable segments
Segment Reporting Information [Line Items]
Revenues	93,218,000	78,752,000	290,009,000	258,106,000
Operating income	$ 26,538,000	18,419,000	$ 89,493,000	76,236,000
Other \| Reportable segments
Segment Reporting Information [Line Items]
Revenues		11,593,000		105,562,000
Operating income		$ 6,927,000		$ 65,075,000

Segment Information - Reconciliation of Segment Gross Contribution to Net Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Costs and expenses:
Cost of services and product development	$ 365,056	$ 336,112	$ 1,099,700	$ 1,060,958
Selling, general and administrative	512,159	447,537	1,545,905	1,396,085
Acquisition and integration charges	1,742	17,114	4,156	96,342
Operating income	69,147	52,724	233,948	130,109
Interest expense and other, net	16,049	27,811	66,716	98,454
Gain (loss) from divested operations	0	13,040	(2,075)	38,500
Provision (benefit) for income taxes	11,710	26,200	(432)	31,719
Net income	41,388	11,753	165,589	38,436
Reportable segments
Costs and expenses:
Operating income	636,505	585,304	$ 1,946,370	1,845,286
Reportable segments \| Maximum
Costs and expenses:
Percent of target bonus allocated to segments			100.00%
Corporate and other expenses
Costs and expenses:
Cost of services and product development	1,059	(258)	$ 4,242	19,669
Selling, general and administrative	512,159	447,537	1,545,905	1,396,085
Depreciation and amortization	52,398	68,187	158,119	203,081
Acquisition and integration charges	1,742	17,114	4,156	96,342
Operating income	$ (567,358)	$ (532,580)	$ (1,712,422)	$ (1,715,177)

Goodwill and Intangible Assets - Changes to Carrying Amount of Goodwill by Reporting Unit (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill impairment	$ 0
Goodwill [Roll Forward]
Beginning balance		$ 2,923,136,000
Foreign currency translation impact		16,571,000
Ending balance	2,939,707,000	2,939,707,000
Goodwill, accumulated impairment losses			$ 0
Research
Goodwill [Roll Forward]
Beginning balance		2,638,418,000
Foreign currency translation impact		16,745,000
Ending balance	2,655,163,000	2,655,163,000
Conferences
Goodwill [Roll Forward]
Beginning balance		187,654,000
Foreign currency translation impact		24,000
Ending balance	187,678,000	187,678,000
Consulting
Goodwill [Roll Forward]
Beginning balance		97,064,000
Foreign currency translation impact		(198,000)
Ending balance	$ 96,866,000	$ 96,866,000

Goodwill and Intangible Assets - Carrying Amounts of Amortizable Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Finite-lived Intangible Assets [Roll Forward]
Gross cost, beginning balance			$ 1,392,861
Intangible assets fully amortized			(104,580)
Foreign currency translation impact			(10,221)
Gross cost, ending balance	$ 1,278,060		1,278,060
Accumulated amortization	(341,747)		(341,747)		$ (350,296)
Finite-lived intangible assets, net	936,313		936,313		1,042,565
Amortization of intangibles	31,694	$ 50,852	97,541	$ 152,625
Customer Relationships
Finite-lived Intangible Assets [Roll Forward]
Gross cost, beginning balance			1,131,656
Intangible assets fully amortized			0
Foreign currency translation impact			(9,810)
Gross cost, ending balance	1,121,846		1,121,846
Accumulated amortization	(255,139)		(255,139)		(184,918)
Finite-lived intangible assets, net	866,707		$ 866,707		946,738
Customer Relationships \| Minimum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			4 years
Customer Relationships \| Maximum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			13 years
Software
Finite-lived Intangible Assets [Roll Forward]
Gross cost, beginning balance			$ 110,701
Intangible assets fully amortized			0
Foreign currency translation impact			(303)
Gross cost, ending balance	110,398		110,398
Accumulated amortization	(55,609)		(55,609)		(38,901)
Finite-lived intangible assets, net	54,789		$ 54,789		71,800
Software \| Minimum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			3 years
Software \| Maximum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			7 years
Content
Finite-lived Intangible Assets [Roll Forward]
Gross cost, beginning balance			$ 98,842
Intangible assets fully amortized			(85,900)
Foreign currency translation impact			(2)
Gross cost, ending balance	12,940		12,940
Accumulated amortization	(9,973)		(9,973)		(92,717)
Finite-lived intangible assets, net	2,967		$ 2,967		6,125
Content \| Minimum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			1 year 6 months
Content \| Maximum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			5 years
Other
Finite-lived Intangible Assets [Roll Forward]
Gross cost, beginning balance			$ 51,662
Intangible assets fully amortized			(18,680)
Foreign currency translation impact			(106)
Gross cost, ending balance	32,876		32,876
Accumulated amortization	(21,026)		(21,026)		(33,760)
Finite-lived intangible assets, net	$ 11,850		$ 11,850		$ 17,902
Other \| Minimum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			2 years
Other \| Maximum
Finite-lived Intangible Assets [Roll Forward]
Finite-lived intangible assets useful life			11 years

Goodwill and Intangible Assets - Estimated Future Amortization Expense By Year From Amortizable Intangibles (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2019 (remaining three months)	$ 31,812
2020	122,864
2021	102,493
2022	92,989
2023	92,989
Thereafter	493,166
Finite-lived intangible assets, net	$ 936,313	$ 1,042,565

Debt - Narrative (Details)	9 Months Ended
Debt - Narrative (Details)	Sep. 30, 2019 USD ($) installment
Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount	$ 800,000,000.0
Debt instrument, fixed interest rate	5.125%
Debt instrument, issue price, percent	100.00%
Debt instrument, redemption, prince, percentage of principal amount that may be redeemed	40.00%
Senior Notes \| Debt instrument, redemption with the proceeds of certain equity offerings
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	105.125%
Senior Notes \| Debt instrument, redemption excluding make whole premium
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	100.00%
Senior Notes \| Debt instrument, redemption due to specific kinds of change of control
Debt Instrument [Line Items]
Debt instrument, redemption price, percentage	101.00%
2016 Agreement
Debt Instrument [Line Items]
Debt instrument, interest, additional interest above eurodollar rate	1.00%
2016 Agreement \| Federal Funds Rate
Debt Instrument [Line Items]
Debt instrument, interest, additional interest above Federal Fund rate	0.50%
Minimum applicable margin rate	0.125%
Maximum applicable margin rate	1.50%
2016 Agreement \| Euro Dollar rate
Debt Instrument [Line Items]
Minimum applicable margin rate	1.125%
Maximum applicable margin rate	2.50%
2016 Agreement \| Term loans \| Bank Term Loan - A Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 1,500,000,000
2016 Agreement \| Revolving credit facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 1,200,000,000
Bank Term Loan - A Facility \| Term loans
Debt Instrument [Line Items]
Line of credit facility, frequency of payments, number of quarterly installments \| installment	16

Debt - Borrowings (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Principal amount outstanding	$ 2,207,480	$ 2,312,092
Less: deferred financing fees	(25,540)	(30,405)
Net balance sheet carrying amount	2,181,940	2,281,687
Revolving credit facility
Debt Instrument [Line Items]
Long-term debt, gross	120,000	155,000
Bank Term Loan - A Facility
Debt Instrument [Line Items]
Long-term debt, gross	1,280,813	1,355,062
Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	800,000	800,000
Other
Debt Instrument [Line Items]
Long-term debt, gross	$ 6,667	$ 2,030

Debt - Footnote to Borrowings (Details) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
Debt - Footnote to Borrowings (Details) $ in Thousands	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2012 loan	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Proceeds from borrowings		$ 5,000	$ 0
Weighted average annual effect rate	4.00%	4.01%
Bank Term Loan - A Facility
Debt Instrument [Line Items]
Floating eurodollar base rate	2.04%	2.04%
Long term debt	$ 1,280,813	$ 1,280,813			$ 1,355,062
Senior Notes
Debt Instrument [Line Items]
Long term debt	$ 800,000	$ 800,000			800,000
Debt instrument, fixed interest rate	5.125%	5.125%
Connecticut Economic Development Program
Debt Instrument [Line Items]
Number of loans \| loan				2
Revolving credit facility
Debt Instrument [Line Items]
Contractual annualized interest rate	1.50%	1.50%
Additional interest above base rate		3.54%
Remaining borrowing capacity	$ 1,100,000	$ 1,100,000
Long term debt	120,000	120,000			$ 155,000
Economic Development Loan 1 \| Connecticut Economic Development Program
Debt Instrument [Line Items]
Long term debt	$ 1,700	$ 1,700
Debt instrument, fixed interest rate	3.00%	3.00%
Debt term				10 years
Proceeds from borrowings		$ 5,000
Economic Development Loan 2 \| Connecticut Economic Development Program
Debt Instrument [Line Items]
Debt instrument, fixed interest rate	1.75%	1.75%
Debt term		10 years
Period payments are deferred		7 years
Possible forgiveness of debt		$ 5,000
Period of possible forgiveness		5 years

Debt - Interest Rate Swaps (Details) $ in Thousands	9 Months Ended
Debt - Interest Rate Swaps (Details) $ in Thousands	Sep. 30, 2019 USD ($) derivative_instrument outstanding_contract	Dec. 31, 2018 USD ($) outstanding_contract
Derivative [Line Items]
Number of contracts \| outstanding_contract	44	142
Interest rate swap contracts total notional value	$ 1,603,351	$ 3,027,375
Interest rate swaps
Derivative [Line Items]
Number of contracts \| derivative_instrument	4,000,000
Interest rate swap contracts total notional value	$ 1,400,000
Term of contract	30 days
Net negative fair value (liability)	$ 80,200
Minimum \| Interest rate swaps
Derivative [Line Items]
Fixed interest rate	2.13%
Maximum \| Interest rate swaps
Derivative [Line Items]
Fixed interest rate	3.04%

Equity - Share Repurchase Program and Share Repurchase Activity (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	May 31, 2015
Stockholders' Equity Note [Abstract]
Stock repurchase program, authorized amount					$ 1,200,000,000
Stock repurchase program, remaining authorized repurchase amount	$ 800,000,000		$ 800,000,000
Number of shares repurchased (in shares)	705,800	51,298	929,311	815,001
Cash paid for repurchased shares	$ 94,878,000	$ 8,129,000	$ 141,436,000	$ 104,400,000
Treasury stock, average price paid per share (in dollars per share)	$ 134.42	$ 140.09	$ 136.05	$ 128.10

Equity - Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Apr. 01, 2018	Jan. 01, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 963,802	$ 921,432	$ 850,757	$ 983,465
Net income	41,388	11,753	165,589	38,436
Other comprehensive income (loss)	(7,785)	1,367	(41,397)	(24,783)
Issuances under stock plans	4,171	3,463	13,248	6,529
Common share repurchases	(94,873)	(7,186)	(126,433)	(104,400)
Stock-based compensation expense	12,954	10,718	57,893	56,018
Ending balance	919,657	941,548	919,657	941,548
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	82	82	82	82
Ending balance	82	82	82	82
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,868,878	1,798,075	1,823,710	1,761,383
Issuances under stock plans	3,538	1,752	3,767	(6,856)
Stock-based compensation expense	12,954	10,718	57,893	56,018
Ending balance	1,885,370	1,810,545	1,885,370	1,810,545
Accumulated Other Comprehensive Loss, Net
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(73,479)	(24,051)	(39,867)	1,508
Other comprehensive income (loss)	(7,785)	1,367	(41,397)	(24,783)
Ending balance	(81,264)	(22,684)	(81,264)	(22,684)
Accumulated Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,879,633	1,659,658	1,755,432	1,647,284
Net income	41,388	11,753	165,589	38,436
Ending balance	1,921,021	1,671,412	1,921,021	1,671,412
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(2,711,312)	(2,512,332)	(2,688,600)	(2,426,792)
Issuances under stock plans	633	1,711	9,481	13,385
Common share repurchases	(94,873)	(7,186)	(126,433)	(104,400)
Ending balance	$ (2,805,552)	$ (2,517,807)	$ (2,805,552)	$ (2,517,807)
Accounting Standards Update 2018-02
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU					$ 0
Accounting Standards Update 2018-02 \| Accumulated Other Comprehensive Loss, Net
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU					591
Accounting Standards Update 2018-02 \| Accumulated Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU					$ (591)
Accounting Standards Update 2016-16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU						$ (13,717)
Accounting Standards Update 2016-16 \| Accumulated Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adoption of ASU						$ (13,717)

Equity - Changes in AOCI/L by Component (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Apr. 01, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 963,802	$ 921,432	$ 850,757	$ 983,465
Change in AOCI/L before reclassifications to income	(6,731)	1,783	(37,146)	35,404
Reclassifications from AOCL/I to income	(1,054)	(416)	(4,251)	(60,187)
Other comprehensive (loss) income, net of tax	(7,785)	1,367	(41,397)	(24,783)
Ending balance	919,657	941,548	919,657	941,548
Interest Rate Swaps
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(46,990)	16,281	(7,770)	2,483
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect				591
Change in AOCI/L before reclassifications to income	(10,285)	969	(46,224)	13,748
Reclassifications from AOCL/I to income	(1,094)	(619)	(4,375)	(191)
Other comprehensive (loss) income, net of tax	(11,379)	350	(50,599)	13,557
Ending balance	(58,369)	16,631	(58,369)	16,631
Defined Benefit Pension Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(5,655)	(5,750)	(5,738)	(5,861)
Change in AOCI/L before reclassifications to income	0	0	0	0
Reclassifications from AOCL/I to income	41	53	124	164
Other comprehensive (loss) income, net of tax	41	53	124	164
Ending balance	(5,614)	(5,697)	(5,614)	(5,697)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(20,834)	(34,582)	(26,359)	4,886
Change in AOCI/L before reclassifications to income	3,553	814	9,078	21,656
Reclassifications from AOCL/I to income	0	150	0	(60,160)
Other comprehensive (loss) income, net of tax	3,553	964	9,078	(38,504)
Ending balance	(17,281)	(33,618)	(17,281)	(33,618)
Accumulated Other Comprehensive Loss, Net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(73,479)	(24,051)	(39,867)	1,508
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect				591
Other comprehensive (loss) income, net of tax	(7,785)	1,367	(41,397)	(24,783)
Ending balance	(81,264)	(22,684)	(81,264)	(22,684)
Accumulated Earnings
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	1,879,633	1,659,658	1,755,432	1,647,284
Ending balance	$ 1,921,021	$ 1,671,412	$ 1,921,021	$ 1,671,412
Accounting Standards Update 2018-02
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Adoption of ASU					$ 0
Accounting Standards Update 2018-02 \| Accumulated Other Comprehensive Loss, Net
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Adoption of ASU					591
Accounting Standards Update 2018-02 \| Accumulated Earnings
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Adoption of ASU					$ (591)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Provision (benefit) for income taxes	$ 11,710	$ 26,200	$ (432)	$ 31,719
Effective income tax rate	22.10%	69.00%	(0.30%)	45.20%
Benefits of future tax deductions for amortization			$ 38,100
Unrecognized tax benefits	$ 87,300		87,300		$ 90,300
Decrease in unrecognized tax benefits is reasonably possible	$ 2,800		$ 2,800

Derivatives and Hedging - Outstanding Derivatives Contracts (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019 USD ($) derivative_instrument outstanding_contract	Dec. 31, 2018 USD ($) outstanding_contract
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	44	142
Notional Amounts	$ 1,603,351	$ 3,027,375
Fair Value Asset (Liability), Net	(80,453)	(12,623)
Unrealized Loss Recorded in AOCI/L	$ (58,369)
Unrealized Loss Recorded in AOCI/L		$ (7,770)
Interest rate swaps
Derivatives, Fair Value [Line Items]
Number of Contracts \| derivative_instrument	4,000,000
Notional Amounts	$ 1,400,000
Designated as hedging instrument \| Other liabilities \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	4	7
Notional Amounts	$ 1,400,000	$ 2,100,000
Fair Value Asset (Liability), Net	(80,233)	(10,681)
Unrealized Loss Recorded in AOCI/L	$ (58,369)
Unrealized Loss Recorded in AOCI/L		$ (7,770)
Not Designated as Hedging Instrument \| Accrued liabilities \| Foreign currency forwards
Derivatives, Fair Value [Line Items]
Number of Contracts \| outstanding_contract	40	135
Notional Amounts	$ 203,351	$ 927,375
Fair Value Asset (Liability), Net	(220)	(1,942)
Unrealized Loss Recorded in AOCI/L	$ 0
Unrealized Loss Recorded in AOCI/L		$ 0

Derivatives and Hedging - Amounts Recognized in the Condensed Consolidated Statements of Operations for Derivative Contracts (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Total expense (income), net	$ 2,863	$ 289	$ (951)	$ 2,553
Interest (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Total expense (income), net	(1,504)	(851)	(6,015)	(262)
Other expense (income), net
Derivative Instruments, Gain (Loss) [Line Items]
Total expense (income), net	$ 4,367	$ 1,140	$ 5,064	$ 2,815

Fair Value Disclosures - Assets And Liabilities Measured At Fair Value On Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Assets:
Assets measured at fair value on a recurring basis	$ 70,541	$ 67,964
Liabilities:
Liabilities measured at fair value on a recurring basis	993,410	858,671
Fair Value, Inputs, Level 1
Assets:
Assets measured at fair value on a recurring basis	8,985	8,956
Fair Value, Inputs, Level 2
Assets:
Assets measured at fair value on a recurring basis	61,556	59,008
Liabilities:
Liabilities measured at fair value on a recurring basis	993,410	858,671
Fair Value, Inputs, Level 2 \| Foreign currency forward contracts
Assets:
Assets measured at fair value on a recurring basis	65	1,318
Liabilities:
Liabilities measured at fair value on a recurring basis	285	3,260
Fair Value, Inputs, Level 2 \| Interest rate swap contracts
Liabilities:
Liabilities measured at fair value on a recurring basis	80,233	10,681
Fair Value, Inputs, Level 2 \| Deferred compensation plan assets
Assets:
Assets measured at fair value on a recurring basis	61,491	57,690
Fair Value, Inputs, Level 2 \| Deferred compensation plan liabilities
Liabilities:
Liabilities measured at fair value on a recurring basis	74,308	68,570
Senior Notes
Liabilities:
Long term debt	800,000	800,000
Senior Notes \| Fair Value, Inputs, Level 2 \| Senior notes
Liabilities:
Liabilities measured at fair value on a recurring basis	$ 838,584	$ 776,160

Employee Benefits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Employee Benefits (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Retirement Benefits [Abstract]
Net periodic pension expense	$ 0.9	$ 0.9	$ 2.6	$ 2.5

Contingencies (Details)	Sep. 30, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Payment obligations under indemnification agreements	$ 0

Subsequent Events - (Details) - TOPO Research LLC - Subsequent Event $ in Millions	Oct. 01, 2019 USD ($)
Subsequent Event [Line Items]
Percent of outstanding membership interests acquired	100.00%
Purchase price	$ 33