MSCI (MSCI) 10-Q 28 Oct 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 20, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Trading Symbol	MSCI
Entity Registrant Name	MSCI INC.
Entity Central Index Key	0001408198
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		82,895,040
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-33812
Entity Tax Identification Number	13-4038723
Entity Address, Address Line One	7 World Trade Center
Entity Address, Address Line Two	250 Greenwich Street, 49th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10007
City Area Code	212
Local Phone Number	804-3900
Entity Interactive Data Current	Yes
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Common stock, par value $0.01 per share
Security Exchange Name	NYSE
Document Quarterly Report	true
Document Transition Report	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 1,302,858	$ 1,506,567
Accounts receivable, net of allowances	429,804	499,268
Prepaid income taxes	63,460	31,590
Prepaid and other assets	46,970	44,352
Total current assets	1,843,092	2,081,777
Property, equipment and leasehold improvements, net	78,965	90,708
Right of use assets	153,727	166,406
Goodwill	1,562,377	1,562,868
Intangible assets, net	240,858	261,487
Equity method investment	190,206
Deferred tax assets	23,773	20,911
Other non-current assets	18,721	20,282
Total assets	4,111,719	4,204,439
Current liabilities:
Accounts payable	4,718	6,498
Income taxes payable	22,039	14,210
Accrued compensation and related benefits	127,605	166,273
Other accrued liabilities	149,005	139,149
Deferred revenue	531,487	574,656
Total current liabilities	834,854	900,786
Long-term debt	3,365,783	3,071,926
Long-term operating lease liabilities	152,812	164,144
Deferred tax liabilities	63,845	66,639
Other non-current liabilities	81,011	77,658
Total liabilities	4,498,305	4,281,153
Commitments and Contingencies (see Note 7)
Shareholders' equity (deficit):
Preferred stock (par value $0.01, 100,000,000 shares authorized; no shares issued)
Common stock (par value $0.01; 750,000,000 common shares authorized; 132,823,285 and 132,419,412 common shares issued and 83,041,856 and 84,794,930 common shares outstanding at September 30, 2020 and December 31, 2019, respectively)	1,328	1,324
Treasury shares, at cost (49,781,429 and 47,624,482 common shares held at September 30, 2020 and December 31, 2019, respectively)	(4,177,563)	(3,565,784)
Additional paid in capital	1,391,837	1,351,031
Retained earnings	2,463,108	2,199,294
Accumulated other comprehensive loss	(65,296)	(62,579)
Total shareholders' equity (deficit)	(386,586)	(76,714)
Total liabilities and shareholders' equity (deficit)	$ 4,111,719	$ 4,204,439

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Financial Condition (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	750,000,000	750,000,000
Common stock, shares issued	132,823,285	132,419,412
Common stock, shares outstanding	83,041,856	84,794,930
Treasury shares	49,781,429	47,624,482

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Operating revenues	$ 425,333	$ 394,251	$ 1,251,729	$ 1,151,190
Operating expenses:
Cost of revenues	70,704	70,486	215,769	224,807
Selling and marketing	52,668	52,107	159,834	159,812
Research and development	24,901	24,310	73,997	71,234
General and administrative	27,613	26,559	86,755	80,434
Amortization of intangible assets	14,333	12,361	42,171	36,167
Depreciation and amortization of property, equipment and leasehold improvements	7,494	7,209	22,524	22,464
Total operating expenses	197,713	193,032	601,050	594,918
Operating income	227,620	201,219	650,679	556,272
Interest income	(475)	(3,673)	(4,729)	(11,104)
Interest expense	37,536	35,922	118,994	107,752
Other expense (income)	1,516	222	45,355	2,839
Other expense (income), net	38,577	32,471	159,620	99,487
Income before provision for income taxes	189,043	168,748	491,059	456,785
Provision for income taxes	6,685	31,765	45,453	15,920
Net income	$ 182,358	$ 136,983	$ 445,606	$ 440,865
Earnings per basic common share	$ 2.18	$ 1.62	$ 5.30	$ 5.21
Earnings per diluted common share	$ 2.16	$ 1.60	$ 5.26	$ 5.15
Weighted average shares outstanding used in computing earnings per share
Basic	83,602	84,765	84,044	84,591
Diluted	84,479	85,550	84,789	85,533

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 182,358	$ 136,983	$ 445,606	$ 440,865
Other comprehensive (loss) income:
Foreign currency translation adjustments	7,058	(5,533)	(3,743)	(4,853)
Income tax effect	(1,124)	1,124	965	1,085
Foreign currency translation adjustments, net	5,934	(4,409)	(2,778)	(3,768)
Pension and other post-retirement adjustments	(245)	134	(27)	103
Income tax effect	83	(64)	88	(34)
Pension and other post-retirement adjustments, net	(162)	70	61	69
Other comprehensive (loss) income, net of tax	5,772	(4,339)	(2,717)	(3,699)
Comprehensive income	$ 188,130	$ 132,644	$ 442,889	$ 437,166

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member]Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2018	$ (166,494)		$ 1,300	$ (3,272,774)	$ 1,306,428	$ 1,856,951		$ (58,399)
Net income	178,192					178,192
Dividends	(55,339)					(55,339)
Dividends paid in shares	93				93
Other comprehensive income (loss), net of tax	1,197							1,197
Common stock issued	23		23
Shares withheld for tax withholding and exercises	(182,385)			(182,385)
Compensation payable in common stock and options	9,590				9,590
Common stock repurchased and held in treasury	(102,081)			(102,081)
Common stock issued to Directors and (held in)/released from treasury	(30)			(30)
Exercise of stock options	726				726
Balance at Mar. 31, 2019	(316,508)		1,323	(3,557,270)	1,316,837	1,979,804		(57,202)
Balance at Dec. 31, 2018	(166,494)		1,300	(3,272,774)	1,306,428	1,856,951		(58,399)
Net income	440,865
Dividends	(163,128)
Balance at Sep. 30, 2019	(147,856)		1,323	(3,559,963)	1,338,194	2,134,688		(62,098)
Balance at Mar. 31, 2019	(316,508)		1,323	(3,557,270)	1,316,837	1,979,804		(57,202)
Net income	125,690					125,690
Dividends	(49,613)					(49,613)
Dividends paid in shares	30				30
Other comprehensive income (loss), net of tax	(557)							(557)
Shares withheld for tax withholding and exercises	(742)			(742)
Compensation payable in common stock and options	10,566				10,566
Common stock issued to Directors and (held in)/released from treasury	(833)			(833)
Exercise of stock options	165				165
Balance at Jun. 30, 2019	(231,802)		1,323	(3,558,845)	1,327,598	2,055,881		(57,759)
Net income	136,983					136,983
Dividends	(58,176)					(58,176)
Dividends paid in shares	36				36
Other comprehensive income (loss), net of tax	(4,339)							(4,339)
Shares withheld for tax withholding and exercises	(1,082)			(1,082)
Compensation payable in common stock and options	10,398				10,398
Common stock issued to Directors and (held in)/released from treasury	(36)			(36)
Exercise of stock options	162				162
Balance at Sep. 30, 2019	(147,856)		1,323	(3,559,963)	1,338,194	2,134,688		(62,098)
Balance at Dec. 31, 2019	(76,714)		1,324	(3,565,784)	1,351,031	2,199,294		(62,579)
Net income	148,125					148,125
Cumulative-effect adjustment		$ 631					$ 631
Dividends	(59,233)					(59,233)
Dividends paid in shares	78				78
Other comprehensive income (loss), net of tax	(9,625)							(9,625)
Common stock issued	4		4
Shares withheld for tax withholding and exercises	(47,195)			(47,195)
Compensation payable in common stock and options	15,333				15,333
Common stock repurchased and held in treasury	(325,699)			(325,699)
Common stock issued to Directors and (held in)/released from treasury	(36)			(36)
Balance at Mar. 31, 2020	(354,331)		1,328	(3,938,714)	1,366,442	2,288,817		(72,204)
Balance at Dec. 31, 2019	(76,714)		1,324	(3,565,784)	1,351,031	2,199,294		(62,579)
Net income	445,606
Dividends	(182,423)
Balance at Sep. 30, 2020	(386,586)		1,328	(4,177,563)	1,391,837	2,463,108		(65,296)
Balance at Mar. 31, 2020	(354,331)		1,328	(3,938,714)	1,366,442	2,288,817		(72,204)
Net income	115,123					115,123
Dividends	(57,360)					(57,360)
Dividends paid in shares	36				36
Other comprehensive income (loss), net of tax	1,136							1,136
Shares withheld for tax withholding and exercises	(603)			(603)
Compensation payable in common stock and options	14,294				14,294
Common stock repurchased and held in treasury	(31,071)			(31,071)
Common stock issued to Directors and (held in)/released from treasury	1,844			1,844
Balance at Jun. 30, 2020	(310,932)		1,328	(3,968,544)	1,380,772	2,346,580		(71,068)
Net income	182,358					182,358
Dividends	(65,830)					(65,830)
Dividends paid in shares	20				20
Other comprehensive income (loss), net of tax	5,772							5,772
Shares withheld for tax withholding and exercises	(2,433)			(2,433)
Compensation payable in common stock and options	11,045				11,045
Common stock repurchased and held in treasury	(206,566)			(206,566)
Common stock issued to Directors and (held in)/released from treasury	(20)			(20)
Balance at Sep. 30, 2020	$ (386,586)		$ 1,328	$ (4,177,563)	$ 1,391,837	$ 2,463,108		$ (65,296)

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Shareholders' Equity (Deficit) (Parenthetical) - $ / shares	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Stockholders Equity [Abstract]
Dividends per common share	$ 0.78	$ 0.68	$ 0.68	$ 0.68	$ 0.58	$ 0.58	$ 2.14	$ 1.84

Condensed Consolidated Statem_7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities
Net income	$ 445,606	$ 440,865
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	42,171	36,167
Stock-based compensation expense	40,381	30,485
Depreciation and amortization of property, equipment and leasehold improvements	22,524	22,464
Amortization of right of use assets	18,061	16,778
Amortization of debt origination fees	3,338	2,956
Loss on extinguishment of debt	44,930
Deferred taxes	(4,622)	(9,844)
Other adjustments	1,680	708
Changes in assets and liabilities:
Accounts receivable	69,848	62,331
Prepaid income taxes	(31,923)	(37,199)
Prepaid and other assets	(2,854)	(3,965)
Accounts payable	(1,882)	(1,482)
Accrued compensation and related benefits	(33,532)	(14,107)
Income taxes payable	6,607	(4,251)
Other accrued liabilities	9,801	(6,795)
Deferred revenue	(43,186)	(57,804)
Long-term operating lease liabilities	(17,017)	(14,774)
Other	5,250	3,347
Net cash provided by operating activities	575,181	465,880
Cash flows from investing activities
Acquisition of equity method investment	(190,816)
Capitalized software development costs	(21,931)	(18,086)
Capital expenditures	(12,152)	(17,216)
Proceeds from the sale of capital equipment		10
Net cash used in investing activities	(224,899)	(35,292)
Cash flows from financing activities
Proceeds from borrowings	1,405,000
Repayment of borrowings	(1,142,382)
Proceeds from exercise of stock options		1,052
Repurchase of common stock held in treasury	(613,566)	(286,290)
Payment of debt issuance costs in connection with debt	(16,693)
Payment of dividends	(181,843)	(165,077)
Net cash used in financing activities	(549,484)	(450,315)
Effect of exchange rate changes	(4,507)	(3,299)
Net decrease in cash	(203,709)	(23,026)
Cash and cash equivalent, beginning of period	1,506,567	904,176
Cash and cash equivalent, end of period	1,302,858	881,150
Supplemental disclosure of cash flow information:
Cash paid for interest	109,834	105,015
Cash paid for income taxes	73,311	65,364
Supplemental disclosure of non-cash investing activities
Property, equipment and leasehold improvements accrued, but not yet paid	3,281	4,189
Supplemental disclosure of non-cash financing activities
Cash dividends declared, but not yet paid	$ 1,505	$ 778

Introduction and Basis of Prese

Introduction and Basis of Presentation	9 Months Ended
	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Introduction and Basis of Presentation	1. INTRODUCTION AND BASIS OF PRESENTATION MSCI Inc., together with its wholly owned subsidiaries (the “Company” or “MSCI”) provides critical decision support tools and services that bring greater transparency to the global financial markets. MSCI’s tools and services include indexes; portfolio construction tools and risk-management services; environmental, social and governance (“ESG”) research and ratings; and real estate benchmarks, return analytics services and market insights; much of which can be accessed by clients through multiple channels and platforms. Basis of Presentation and Use of Estimates These unaudited condensed consolidated financial statements include the accounts of MSCI and its wholly owned subsidiaries and include all adjustments of a normal, recurring nature necessary to state fairly the financial condition as of September 30, 2020 and December 31, 2019, the results of operations, comprehensive income and shareholders’ equity (deficit) for the three and nine months ended September 30, 2020 and 2019 and cash flows for the nine months ended September 30, 2020 and 2019. The unaudited condensed consolidated statement of financial condition and related financial statement information as of December 31, 2019 have been derived from the 2019 audited consolidated financial statements but do not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes included in MSCI’s Annual Report on Form 10-K for the year ended December 31, 2019. The results of operations for interim periods are not necessarily indicative of results for the entire year. The Company’s unaudited condensed consolidated financial statements are prepared in accordance with GAAP. These accounting principles require the Company to make certain estimates and judgments that can affect the reported amounts of assets and liabilities as of the date of the unaudited condensed consolidated financial statements, as well as the reported amounts of revenue and expenses during the periods presented. Significant estimates and assumptions made by management include the deferral and recognition of revenue, research and development and software capitalization, assessment of impairment of long-lived assets, accrued compensation, income taxes, incremental borrowing rates and other matters that affect the unaudited condensed consolidated financial statements and related disclosures. The Company believes that estimates used in the preparation of these unaudited condensed consolidated financial statements are reasonable; however, actual results could differ materially from these estimates. Intercompany balances and transactions are eliminated in consolidation. Concentrations For the nine months ended September 30, 2020 and 2019, BlackRock, Inc. accounted for 10.9% and 11.5% of the Company’s consolidated operating revenues, respectively. For the nine months ended September 30, 2020 and 2019, BlackRock, Inc. accounted for 17.8% and 18.9% of the Index segment operating revenues, respectively. No single customer represented 10.0% or more of operating revenues within the Analytics and All Other segments for the nine months ended September 30, 2020 and 2019. Allowance for Credit Losses on Accounts Receivable Following the adoption of Accounting Standards Update No. 2016-13, “ Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Changes in the allowance for credit losses on doubtful accounts receivable from December 31, 2018 to September 30, 2020 were as follows: Amount (in Balance as of December 31, 2018 $ 1,027 Addition (reduction) to credit loss expense 1,024 Write-offs, net of recoveries (336 ) Balance as of December 31, 2019 $ 1,715 Addition (reduction) to credit loss expense 1,042 Adjustments and write-offs, net of recoveries (1,434 ) Balance as of September 30, 2020 $ 1,323

Recent Accounting Standards Upd

Recent Accounting Standards Updates	9 Months Ended
	Sep. 30, 2020
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Standards Updates	2. RECENT ACCOUNTING STANDARDS UPDATES In June 2016, the FASB issued Accounting Standards Update No. 2016-13, “Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” The FASB issued Accounting Standards Update No. 2018-19 , “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” “Financial Instruments-Credit Losses (Topic 326): Targeted Transition Relief,” “Financial Instruments-Credit Losses (Topic 326): Effective Dates,” “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” The Company adopted ASU 2016-13 and the related clarifications effective January 1, 2020. The adoption did not have a material effect on the Company’s condensed consolidated financial statements. In January 2017, the FASB issued Accounting Standards Update No. 2017-04, “Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment,”

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Revenue Recognition	3. REVENUE RECOGNITION MSCI’s revenues are characterized by product type, which broadly reflects the nature of how they are recognized. The Company’s revenue types are recurring subscription, asset-based fees and non-recurring revenues. The Company also reports revenues by segment. The tables that follow present the disaggregated revenues for the periods indicated: For the Three Months ended September 30, 2020 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 146,387 $ 126,251 $ 40,552 $ 313,190 Asset-based fees 100,371 — — 100,371 Non-recurring 8,933 2,086 753 11,772 Total $ 255,691 $ 128,337 $ 41,305 $ 425,333 For the Nine Months ended September 30, 2020 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 431,631 $ 376,505 $ 119,363 $ 927,499 Asset-based fees 288,642 — — 288,642 Non-recurring 27,582 4,903 3,103 35,588 Total $ 747,855 $ 381,408 $ 122,466 $ 1,251,729 For the Three Months ended September 30, 2019 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 133,403 $ 122,120 $ 32,585 $ 288,108 Asset-based fees 96,013 — — 96,013 Non-recurring 8,011 1,483 636 10,130 Total $ 237,427 $ 123,603 $ 33,221 $ 394,251 For the Nine Months ended September 30, 2019 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 393,222 $ 363,929 $ 102,470 $ 859,621 Asset-based fees 265,554 — — 265,554 Non-recurring 18,974 4,790 2,251 26,015 Total $ 677,750 $ 368,719 $ 104,721 $ 1,151,190 The tables that follow present the change in accounts receivable and in deferred revenue between the dates indicated: Accounts receivable Deferred revenue (in thousands) Opening (12/31/2019) $ 499,268 $ 574,656 Closing (09/30/2020) 429,804 531,487 Increase/(decrease) $ (69,464 ) $ (43,169 ) Accounts receivable Deferred revenue (in thousands) Opening (12/31/2018) $ 473,433 $ 537,977 Closing (09/30/2019) 409,519 479,371 Increase/(decrease) $ (63,914 ) $ (58,606 ) The amounts of revenue recognized in the periods that were included in the opening current deferred revenue, which reflects contract liability amounts, were $494.4 million and $464.3 million for the nine months ended September 30, 2020 and 2019, respectively. The difference between the opening and closing balances of the Company’s deferred revenue was primarily driven by an increase in the amortization of deferred revenue to operating revenues, partially offset by an increase in billings. MSCI had an insignificant long-term deferred revenue balance as of September 30, 2020, reflected as a part of “Other non-current liabilities” on its Unaudited Condensed Consolidated Statement of Financial Condition. For contracts that have a duration of one year or less, the Company has not disclosed either the remaining performance obligation as of the end of the reporting period or when the Company expects to recognize the revenue. The remaining performance obligations for contracts that have a duration of greater than one year and the periods in which they are expected to be recognized are as follows: As of September 30, 2020 (in thousands) First 12-month period $ 321,008 Second 12-month period 174,710 Third 12-month period 61,190 Periods thereafter 14,596 Total $ 571,504

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Earnings Per Common Share	4. EARNINGS PER COMMON SHARE Basic earnings per share (“EPS”) is computed by dividing net income by the weighted average number of common shares outstanding during the period. Common shares outstanding include common stock and vested restricted stock unit awards where recipients have satisfied either the explicit vesting terms or retirement-eligible requirements. Diluted EPS reflects the assumed conversion of all dilutive securities. The following table presents the computation of basic and diluted EPS: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands, except per share data) Net income $ 182,358 $ 136,983 $ 445,606 $ 440,865 Basic weighted average common shares outstanding 83,602 84,765 84,044 84,591 Effect of dilutive securities: Stock options and restricted stock units 877 785 745 942 Diluted weighted average common shares outstanding 84,479 85,550 84,789 85,533 Earnings per basic common share $ 2.18 $ 1.62 $ 5.30 $ 5.21 Earnings per diluted common share $ 2.16 $ 1.60 $ 5.26 $ 5.15

Property, Equipment and Leaseho

Property, Equipment and Leasehold Improvements, Net	9 Months Ended
	Sep. 30, 2020
Property Plant And Equipment [Abstract]
Property, Equipment and Leasehold Improvements, Net	5. PROPERTY, EQUIPMENT AND LEASEHOLD IMPROVEMENTS, NET Property, equipment and leasehold improvements, net consisted of the following as of the specified dates: As of September 30, December 31, 2020 2019 (in thousands) Computer & related equipment $ 184,237 $ 185,794 Furniture & fixtures 14,961 12,478 Leasehold improvements 57,438 52,339 Work-in-process 2,011 8,667 Subtotal 258,647 259,278 Accumulated depreciation and amortization (179,682 ) (168,570 ) Property, equipment and leasehold improvements, net $ 78,965 $ 90,708 Depreciation and amortization expense of property, equipment and leasehold improvements was $7.5 million and $7.2 million for the three months ended September 30, 2020 and 2019, respectively. Depreciation and amortization expense of property, equipment and leasehold improvements was $22.5 million for both the nine months ended September 30, 2020 and 2019.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net	9 Months Ended
	Sep. 30, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets, Net	6. GOODWILL AND INTANGIBLE ASSETS, NET Goodwill The following table presents goodwill by reportable segment: (in thousands) Index Analytics All Other Total Goodwill at December 31, 2019 $ 1,204,694 $ 290,976 $ 67,198 $ 1,562,868 Foreign exchange translation adjustment (805 ) — 314 (491 ) Goodwill at September 30, 2020 $ 1,203,889 $ 290,976 $ 67,512 $ 1,562,377 The Company completed its annual goodwill impairment test as of July 1, 2020 on its Index, Analytics, ESG and Real Estate operating segments, and no impairments were noted. The Company performed a step zero, qualitative impairment test on these four operating segments and determined that it was more likely than not that the fair value for each was not less than the carrying value. See Note 11, “Segment Information,” for further descriptions of the operating segments. Intangible Assets , Net Amortization expense related to intangible assets for the three months ended September 30, 2020 and 2019 was $14.3 million and $12.4 million, respectively. The amortization expense of acquired intangible assets for the three months ended September 30, 2020 and 2019 was $8.3 million and $8.6 million, respectively. The amortization expense of internally developed capitalized software for the three months ended September 30, 2020 and 2019 was $6.0 million and $3.8 million, respectively. Amortization expense related to intangible assets for the nine months ended September 30, 2020 and 2019 was $42.2 million and $36.2 million, respectively. The amortization expense of acquired intangible assets for the nine months ended September 30, 2020 and 2019 was $25.7 million and $26.0 million, respectively. The amortization expense of internally developed capitalized software for the nine months ended September 30, 2020 and 2019 was $16.5 million and $10.2 million, respectively. The gross carrying and accumulated amortization amounts related to the Company’s intangible assets were as follows: As of September 30, December 31, 2020 2019 (in thousands) Gross intangible assets: Customer relationships $ 356,700 $ 356,700 Trademarks/trade names 207,300 207,300 Technology/software 283,684 263,719 Proprietary data 28,627 28,627 Subtotal 876,311 856,346 Foreign exchange translation adjustment (8,154 ) (7,615 ) Total gross intangible assets $ 868,157 $ 848,731 Accumulated amortization: Customer relationships $ (248,011 ) $ (231,665 ) Trademarks/trade names (140,924 ) (133,305 ) Technology/software (224,928 ) (209,878 ) Proprietary data (15,278 ) (13,963 ) Subtotal (629,141 ) (588,811 ) Foreign exchange translation adjustment 1,842 1,567 Total accumulated amortization $ (627,299 ) $ (587,244 ) Net intangible assets: Customer relationships $ 108,689 $ 125,035 Trademarks/trade names 66,376 73,995 Technology/software 58,756 53,841 Proprietary data 13,349 14,664 Subtotal 247,170 267,535 Foreign exchange translation adjustment (6,312 ) (6,048 ) Total net intangible assets $ 240,858 $ 261,487 The following table presents the estimated amortization expense for the remainder of the year ending December 31, 2020 and succeeding years: Years Ending December 31, Amortization Expense (in thousands) Remainder of 2020 $ 14,995 2021 57,163 2022 49,862 2023 38,955 2024 34,202 Thereafter 45,681 Total $ 240,858

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. COMMITMENTS AND CONTINGENCIES Legal matters . From time to time, the Company is party to various litigation matters incidental to the conduct of its business. The Company is not presently party to any legal proceedings the resolution of which the Company believes would have a material effect on its business, operating results, financial condition or cash flows. Senior Unsecured Notes. The Company had an aggregate of $3,400.0 million in senior unsecured notes (collectively, the “Senior Notes”) outstanding at September 30, 2020, consisting of five discrete private offerings presented in the table below: Principal Amount Outstanding at Carrying Value at Carrying Value at Fair Value at Fair Value at Maturity Date September 30, 2020 September 30, 2020 December 31, 2019 September 30, 2020 December 31, 2019 (in thousands) Long-term debt 5.25% senior unsecured notes due 2024 November 15, 2024 $ - $ - $ 297,835 $ - $ 309,225 5.75% senior unsecured notes due 2025 August 15, 2025 - - 794,063 - 840,872 4.75% senior unsecured notes due 2026 August 1, 2026 500,000 496,090 495,587 518,330 525,800 5.375% senior unsecured notes due 2027 May 15, 2027 500,000 495,656 495,168 533,490 541,300 4.000% senior unsecured notes due 2029 November 15, 2029 1,000,000 990,091 989,273 1,051,560 1,018,820 3.625% senior unsecured notes due 2030 September 1, 2030 400,000 395,340 - 413,764 - 3.875% senior unsecured notes due 2031 February 15, 2031 1,000,000 988,606 - 1,042,670 - Total long-term debt $ 3,400,000 $ 3,365,783 $ 3,071,926 $ 3,559,814 $ 3,236,017 Interest payments attributable to the Senior Notes are due as presented in the following table: First semi-annual interest payment date Second semi- annual interest payment date Senior Notes 4.75% senior unsecured notes due 2026 February 1 August 1 5.375% senior unsecured notes due 2027 May 15 November 15 4.000% senior unsecured notes due 2029 May 15 November 15 3.625% senior unsecured notes due 2030 (1) March 1 September 1 3.875% senior unsecured notes due 2031 (2) June 1 December 1 (1) (2) The first payment occurring on December 1, 2020. The fair market value of the Company’s debt obligations is determined in accordance with accounting standards related to the determination of fair value and represents Level 2 valuations, which are based on one or more quoted prices in markets that are not considered to be active or for which all significant inputs are observable, either directly or indirectly. The Company utilizes the market approach and obtains security pricing from a vendor who uses broker quotes and third-party pricing services to determine fair values. The $500.0 million aggregate principal amount of 4.75% senior unsecured notes due 2026 (the “2026 Senior Notes”) are scheduled to mature and be paid in full on August 1, 2026. At any time prior to August 1, 2021, the Company may redeem all or part of the 2026 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption. In addition, the Company may redeem all or part of the 2026 Senior Notes, together with accrued and unpaid interest, on or after August 1, 2021, at redemption prices set forth in the indenture governing the 2026 Senior Notes. The $500.0 million aggregate principal amount of 5.375% senior unsecured notes due 2027 (the “2027 Senior Notes”) are scheduled to mature and be paid in full on May 15, 2027. the 2027 Senior Notes. At any time prior to May 15, 2021, the Company may use the proceeds of certain equity offerings to redeem up to 35 % of the aggregate principal amount of the 2027 Senior Notes, including any permitted additional notes, at a redemption price equal to 105.375 % of the principal amount plus accrued and unpaid interest, if any, to the redemption date. The $1,000.0 million aggregate principal amount of 4.000% senior unsecured notes due 2029 (the “2029 Senior Notes”) are scheduled to mature and be paid in full on November 15, 2029. At any time prior to November 15, 2024, the Company may redeem all or part of the 2029 Senior Notes at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption. In addition, the Company may redeem all or part of the 2029 Senior Notes, together with accrued and unpaid interest, on or after November 15, 2024, at redemption prices set forth in the indenture governing the 2029 Senior Notes. At any time prior to November 15, 2022, the Company may use the proceeds of certain equity offerings to redeem up to 35% of the aggregate principal amount of the 2029 Senior Notes, including any permitted additional notes, at a redemption price equal to 104.000% of the principal amount plus accrued and unpaid interest, if any, to the redemption date. On March 4, 2020, the Company issued $400.0 million aggregate principal amount of 3.625% senior unsecured notes due 2030 (the “2030 Senior Notes”) in a private offering that was exempt from the registration requirements of the Securities Act of 1933, as amended. The Company used a portion of the net proceeds from the 2030 Senior Notes to redeem the $300.0 million aggregate principal amount that remained outstanding on its 5.250% senior unsecured notes due 2024 (the “2024 Senior Notes”). The early redemption of the 2024 Senior Notes resulted in a $10.0 million loss on debt extinguishment recorded in other expense (income), which included a redemption price of approximately $7.9 million (as set forth in the indenture governing the terms of the 2024 Senior Notes) and the write-off of approximately $2.1 million of unamortized debt issuance costs associated with the 2024 Senior Notes. The 2030 Senior Notes are scheduled to mature and be paid in full on September 1, 2030. At any time prior to March 1, 2025, the Company may redeem all or part of the 2030 Senior Notes at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption. In addition, the Company may redeem all or part of the 2030 Senior Notes, together with accrued and unpaid interest, on or after March 1, 2025, at redemption prices set forth in the indenture governing the 2030 Senior Notes. At any time prior to March 1, 2023, the Company may use the proceeds of certain equity offerings to redeem up to 35% of the aggregate principal amount of the 2030 Senior Notes, including any permitted additional notes, at a redemption price equal to 103.625% of the principal amount plus accrued and unpaid interest, if any, to the redemption date. On May 26, 2020, the Company issued $1,000.0 million aggregate principal amount of 3.875% senior unsecured notes due 2031 (the “2031 Senior Notes”) in a private offering that was exempt from the registration requirements of the Securities Act of 1933, as amended. The Company used a portion of the net proceeds from the 2031 Senior Notes for the early redemption of all of the outstanding $800.0 million aggregate principal amount of 5.75 The 2031 Senior Notes are scheduled to mature and be paid in full on February 15, 2031. At any time prior to June 1, 2025, the Company may redeem all or part of the 2031 Senior Notes at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest, if any, to, but excluding, the redemption date. In addition, the Company may redeem all or part of the 2031 Senior Notes, together with accrued and unpaid interest, on or after June 1, 2025, at redemption prices set forth in the indenture governing the 2031 Senior Notes. At any time prior to June 1, 2023, the Company may use the proceeds of certain equity offerings to redeem up to 35% of the aggregate principal amount of the 2031 Senior Notes, including any permitted additional notes, at a redemption price equal to 103.875% of the principal amount plus accrued and unpaid interest, if any, to, but excluding, the redemption date, so long as at least 50% of the aggregate principal amount of all notes (excluding any additional notes, if any) issued under the indenture governing the 2031 Senior Notes remain outstanding after each such redemption occurs. Revolver. On November 20, 2014, the Company entered into a $200.0 million senior unsecured revolving credit agreement (as amended, the “Revolving Credit Agreement”) with a syndicate of banks. The Revolving Credit Agreement had an initial term of five years with an option to extend for two additional one-year terms. On August 4, 2016, the Company entered into Amendment No. 1 (the “First Amendment”) to the Revolving Credit Agreement. The First Amendment, among other things, (i) increased aggregate commitments available to be borrowed to $220.0 million, (ii) increased the maximum consolidated leverage ratio and (iii) extended the initial term to August 2021 with an option to extend for an additional one-year one-year Third Amendment, among other things, (i) increased aggregate commitments available to be borrowed to $ 400.0 million, (ii) extended the term to November 2024 with an option to extend for an additional one-year term, (iii) decreased the applicable rate and applicable fee rate for loans and commitments and (iv) amended certain restrictive covenants that limit, among other things, the Company’s financial flexibility. At September 30, 2020 , the Revolving Credit Agreement was undrawn. In connection with the closings of the Senior Notes offerings and entry into the Revolving Credit Agreement and the First, Second and Third Amendments, the Company paid certain financing fees which, together with the existing fees related to prior credit facilities, are being amortized over their related lives. At September 30, 2020, $36.1 million of the deferred financing fees remain unamortized, $0.5 million of which is included in “Prepaid and other assets,” $1.4 million of which is included in “Other non-current assets” and $34.2 million of which is grouped and presented as part of “Long-term debt” on the Unaudited Condensed Consolidated Statement of Financial Condition.

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Leases	8. LEASES The Company recognized a total of $7.5 million and $7.2 million of operating lease expenses for the three months ended September 30, 2020 and 2019, respectively. The Company recognized a total of $25.4 million and $21.7 million of operating lease expenses for the nine months ended September 30, 2020 and 2019, respectively. The amounts associated with variable lease costs, short-term lease costs and sublease income were not material for any of the three and nine months ended September 30, 2020 and 2019. Future minimum commitments for the Company’s operating leases in place as of September 30, 2020, the interest and other relevant line items in the Unaudited Condensed Consolidated Statement of Financial Condition are as follows: Maturity of Lease Liabilities Operating (in thousands) Leases Remainder of 2020 $ 5,544 2021 28,598 2022 25,025 2023 23,955 2024 18,651 Thereafter 103,126 Total lease payments $ 204,899 Less: Interest (30,596 ) Present value of lease liabilities $ 174,303 Other accrued liabilities $ 21,491 Long-term operating lease liabilities $ 152,812 Lease term and discount rate for the Company’s operating leases in place as of September 30, 2020 are as follows: As of September 30, Lease Term and Discount Rate 2020 Weighted-average remaining lease term (years) 9.18 Weighted-average discount rate 3.41 % Other information for the Company’s operating leases in place for the nine months ended September 30, 2020 are as follows: Nine Months Ended Other Information September 30, (in thousands) 2020 Operating cash flows used for operating leases $ 22,735 Leased assets obtained in exchange for new operating lease liabilities $ 7,491

Shareholders' Equity (Deficit)

Shareholders' Equity (Deficit)	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Shareholders' Equity (Deficit)	9. SHAREHOLDERS’ EQUITY (DEFICIT) Return of capital . On October 26, 2016, the Board of Directors approved a stock repurchase program for the purchase of up to $750.0 million worth of shares of the Company’s common stock (together with the amount then remaining under a previously existing share repurchase program, the “2016 Repurchase Program”). On May 1, 2018, the Board of Directors authorized an additional stock repurchase program for the purchase of up to $1,000.0 million worth of shares of the Company’s common stock in addition to the $523.1 million of authorization then remaining under the 2016 Repurchase Program (the “2018 Repurchase Program”). On October 29, 2019, the Board of Directors authorized an additional stock repurchase program for the purchase of up to $750.0 million worth of shares of MSCI’s common stock in addition to the $706.1 million of authorization remaining under the 2018 Repurchase Program (the “2019 Repurchase Program”) for a total of $1,456.1 million of stock repurchase authorization. Share repurchases made pursuant to the 2019 Repurchase Program may take place in the open market or in privately negotiated transactions from time to time based on market and other conditions. This authorization may be modified, suspended or terminated by the Board of Directors at any time without prior notice. As of September 30, 2020, there was $892.8 million of available authorization remaining under the 2019 Repurchase Program. The following table provides information with respect to repurchases of the Company’s common stock made on the open market: Nine Months Ended Average Price Paid Per Share Total Number of Shares Repurchased Dollar Value of Shares Repurchased (in thousands) September 30, 2020 $ 278.69 2,021 $ 563,336 September 30, 2019 $ 147.97 690 $ 102,081 The following table presents dividends declared per common share as well as total amounts declared, distributed and deferred for the periods indicated: Dividends (in thousands, except per share amounts) Per Share Declared Distributed (Released)/Deferred 2020 Three Months Ended March 31, $ 0.68 $ 59,233 $ 59,455 $ (222 ) Three Months Ended June 30, 0.68 57,360 57,068 292 Three Months Ended September 30, 0.78 65,830 65,454 376 Total $ 2.14 $ 182,423 $ 181,977 $ 446 2019 Three Months Ended March 31, $ 0.58 $ 55,339 $ 57,988 $ (2,649 ) Three Months Ended June 30, 0.58 49,613 49,365 248 Three Months Ended September 30, 0.68 58,176 57,882 294 Total $ 1.84 $ 163,128 $ 165,235 $ (2,107 ) Common Stock. The following table presents activity related to shares of common stock issued and repurchased during the nine months ended September 30, 2020: Common Stock Treasury Common Stock Issued Stock Outstanding Balance at December 31, 2019 132,419,412 (47,624,482 ) 84,794,930 Dividend payable/paid 259 (120 ) 139 Common stock issued 377,843 — 377,843 Shares withheld for tax withholding — (153,923 ) (153,923 ) Shares repurchased under stock repurchase programs — (1,309,878 ) (1,309,878 ) Shares issued to directors 21 — 21 Balance at March 31, 2020 132,797,535 (49,088,403 ) 83,709,132 Dividend payable/paid 114 (114 ) — Common stock issued 10,101 — 10,101 Shares withheld for tax withholding — (1,838 ) (1,838 ) Shares repurchased under stock repurchase programs — (113,494 ) (113,494 ) Shares issued to directors 2,229 27,284 29,513 Balance at June 30, 2020 132,809,979 (49,176,565 ) 83,633,414 Dividend payable/paid 54 (54 ) — Common stock issued 13,252 — 13,252 Shares withheld for tax withholding — (6,779 ) (6,779 ) Shares repurchased under stock repurchase programs — (598,031 ) (598,031 ) Shares issued to directors — — — Balance at September 30, 2020 132,823,285 (49,781,429 ) 83,041,856

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	10. INCOME TAXES The Company’s provision for income taxes was $45.5 million and $15.9 million for the nine months ended September 30, 2020 and 2019, respectively. These amounts reflect effective tax rates of 9.3% and 3.5% for the nine months ended September 30, 2020 and 2019, respectively. The effective tax rate of 9.3% for the nine months ended September 30, 2020 reflects the Company’s estimate of the effective tax rate for the period and was impacted by certain discrete items totaling $61.7 million. For the nine months ended September 30, 2020, these discrete items primarily related to $21.9 million of excess tax benefits recognized on the conversion of equity awards The effective tax rate of 3.5% for the nine months ended September 30, 2019 reflects the Company’s estimate of the effective tax rate for the period and was impacted by certain discrete items totaling $82.7 million. For the nine months ended September 30, 2019, these discrete items primarily related to $66.6 million of excess tax benefits recognized on the conversion during the period of certain multi-year restricted stock units that were subject to the achievement of multi-year total shareholder return targets (performance targets subject to market conditions) granted in 2016 (“2016 multi-year PSUs”) and $10.8 million of excess tax benefits related to the conversion of other equity awards recognized during the period. In addition, the effective tax rate was impacted by a beneficial geographic mix of earnings. During the nine months ended September 30, 2020, a number of countries enacted economic stimulus laws including the CARES Act in the U.S. The Company has evaluated the laws that were passed during the nine months ended September 30, 2020 and does not believe the laws have a material impact on the Company’s effective tax rate or cash flows. A number of the laws, however, have enabled the Company to defer certain eligible tax payments that would have fallen due in earlier quarters. The Company is under examination by the IRS and other tax authorities in certain jurisdictions, including foreign jurisdictions, such as the United Kingdom, Switzerland and India, and states in which the Company has significant operations, such as New York. The tax years currently under examination vary by jurisdiction but include years ranging from 2007 through 2019. The Company regularly assesses the likelihood of additional assessments in each of the taxing jurisdictions in which it files income tax returns. The Company has established unrecognized tax benefits that the Company believes are adequate in relation to the potential for additional assessments. Once established, the Company adjusts unrecognized tax benefits only when more information is available or when an event occurs necessitating a change. As part of the Company’s periodic review of unrecognized tax benefits and based on new information regarding the status of federal and state examinations, the Company’s unrecognized tax benefits were remeasured. Based on the current status of income tax audits, the total amount of unrecognized benefits may decrease by approximately $9.6 million in the next twelve months as a result of the resolution of tax examinations.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Segment Information	11. SEGMENT INFORMATION ASC Subtopic 280-10, “Segment Reporting,” establishes standards for reporting information about operating segments. Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker, or CODM, in deciding how to allocate resources and assess performance. MSCI’s Chief Executive Officer and its President and Chief Operating Officer, who are together considered to be its CODM, review financial information presented on an operating segment basis for purposes of making operating decisions and assessing financial performance. The CODM measures and evaluates reportable segments based on segment operating revenues as well as Adjusted EBITDA and other measures. The Company excludes the following items from segment Adjusted EBITDA: provision for income taxes, other expense (income), net, depreciation and amortization of property, equipment and leasehold improvements, amortization of intangible assets and, at times, certain other transactions or adjustments, including the impact related to the vesting of the 2016 Multi-Year PSUs, that the CODM does not consider for the purposes of making decisions to allocate resources among segments or to assess segment performance. Although these amounts are excluded from segment Adjusted EBITDA, they are included in reported consolidated net income and are included in the reconciliation that follows. The Company’s computation of segment Adjusted EBITDA may not be comparable to other similarly titled measures computed by other companies because all companies do not calculate segment Adjusted EBITDA in the same fashion. Operating revenues and expenses directly associated with each segment are included in determining its operating results. Other expenses that are not directly attributable to a particular segment are based upon allocation methodologies, including time estimates, revenue, headcount, sales targets, data center consumption and other relevant usage measures. Due to the integrated structure of MSCI’s business, certain costs incurred by one segment may benefit other segments. A segment may use the content and data produced by another segment without incurring an arm’s-length intersegment charge. The CODM does not review any information regarding total assets on an operating segment basis. Operating segments do not record intersegment revenues, and, accordingly, there is none to be reported. The accounting policies for segment reporting are the same as for MSCI as a whole. The Company has five operating segments: Index, Analytics, ESG, Real Estate and The Burgiss Group, LLC (“Burgiss”). The Index operating segment is a provider of primarily equity indexes. The indexes are used in many areas of the investment process, including index-linked product creation (e.g., Exchange Traded Funds (“ETFs”) and futures and options), performance benchmarking, portfolio construction and rebalancing, broker-dealer structured products and asset allocation. The Analytics operating segment offers risk management, performance attribution and portfolio management content, applications and services that provide clients with an integrated view of risk and return and an analysis of market, credit, liquidity and counterparty risk across all major asset classes, spanning short-, medium- and long-term time horizons. Clients access Analytics content through MSCI’s own proprietary applications and application programming interfaces, third-party applications or directly through their own platforms. Additionally, the Analytics operating segment also provides various managed services to help clients operate more efficiently, including consolidation of client portfolio data from various sources, review and reconciliation of input data and results, and customized reporting. The ESG operating segment offers products and services that help institutional investors understand how ESG considerations can impact the long-term risk and return of their portfolio and individual security-level investments. In addition, MSCI ESG Research data and ratings are used in the construction of equity and fixed income indexes to help institutional investors more effectively benchmark ESG investment performance, issue index-based investment products, as well as manage, measure and report on ESG mandates. The Real Estate operating segment offers research, reporting, market data and benchmarking offerings that provide real estate performance analysis for funds, investors and managers. Real Estate performance and risk analytics range from enterprise-wide to property-specific analysis. The Real Estate operating segment also provides business intelligence to real estate owners, managers, developers and brokers worldwide. The Burgiss operating segment represents the Company’s equity method investment in Burgiss, a global provider of investment decision support tools for private capital. See Note 12, “Equity Method Investments,” for further information. The operating segments of ESG, Real Estate and Burgiss do not individually meet the segment reporting thresholds and have been combined and presented as part of All Other for disclosure purposes. Burgiss is an equity-method investment, therefore, the All Other segment does not include the Company’s proportionate share of operating revenues and Adjusted EBITDA related to Burgiss. The Company’s proportionate share of Burgiss’s equity earnings is not a component of Adjusted EBITDA as it is reported as a component of other (expense) income, net. The following table presents operating revenue by reportable segment for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands) Operating revenues Index $ 255,691 $ 237,427 $ 747,855 $ 677,750 Analytics 128,337 123,603 381,408 368,719 All Other 41,305 33,221 122,466 104,721 Total $ 425,333 $ 394,251 $ 1,251,729 $ 1,151,190 The following table presents segment profitability and a reconciliation to net income for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands) Index Adjusted EBITDA $ 194,720 $ 177,680 $ 561,563 $ 493,806 Analytics Adjusted EBITDA 45,056 37,797 127,540 113,266 All Other Adjusted EBITDA 9,671 5,312 26,271 23,220 Total operating segment profitability 249,447 220,789 715,374 630,292 2016 Multi-Year PSUs grant payroll tax expense — — — 15,389 Amortization of intangible assets 14,333 12,361 42,171 36,167 Depreciation and amortization of property, equipment and leasehold improvements 7,494 7,209 22,524 22,464 Operating income 227,620 201,219 650,679 556,272 Other expense (income), net 38,577 32,471 159,620 99,487 Provision for income taxes 6,685 31,765 45,453 15,920 Net income $ 182,358 $ 136,983 $ 445,606 $ 440,865 Revenue by geography is based on the shipping address of the ultimate customer utilizing the product. The following table presents revenue by geographic area for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands) Operating revenues Americas: United States $ 180,206 $ 177,154 $ 537,071 $ 516,568 Other 18,039 15,878 52,686 48,669 Total Americas 198,245 193,032 589,757 565,237 Europe, the Middle East and Africa ("EMEA"): United Kingdom 65,155 60,856 193,042 174,984 Other 90,539 80,022 268,677 237,745 Total EMEA 155,694 140,878 461,719 412,729 Asia & Australia: Japan 19,885 18,171 59,002 52,838 Other 51,509 42,170 141,251 120,386 Total Asia & Australia 71,394 60,341 200,253 173,224 Total $ 425,333 $ 394,251 $ 1,251,729 $ 1,151,190 Long-lived assets consist of property, equipment, leasehold improvements, goodwill and intangible assets, net of accumulated depreciation and amortization. The following table presents long-lived assets by geographic area on the dates indicated: As of September 30, December 31, 2020 2019 (in thousands) Long-lived assets Americas: United States $ 1,754,130 $ 1,781,667 Other 5,026 6,398 Total Americas 1,759,156 1,788,065 EMEA: United Kingdom 77,802 81,338 Other 36,510 36,433 Total EMEA 114,312 117,771 Asia & Australia: Japan 378 398 Other 8,354 8,829 Total Asia & Australia 8,732 9,227 Total $ 1,882,200 $ 1,915,063

Equity Method Investment

Equity Method Investment	9 Months Ended
	Sep. 30, 2020
Equity Method Investments And Joint Ventures [Abstract]
Equity Method Investment	12. EQUITY METHOD INVESTMENT In January 2020, MSCI entered into a strategic relationship with Burgiss, a global provider of investment decision support tools for private capital. The Company acquired a 40% non-controlling interest for $190.8 million, including capitalized costs, which is accounted for as an equity method investment with the Company’s share of Burgiss’ earnings being recognized in “Other expense (income), net” in the Condensed Consolidated Statements of Income. The Company is applying a policy election to recognize its share of Burgiss’ earnings on a three-month lag. Accordingly, the Company has recognized in its results of operations an immaterial amount in earnings related to its investment in Burgiss in both the three months and nine months ended September 30, 2020. MSCI has also elected to apply the nature of the distribution approach to determine the classification of the distributions it receives from its equity method investee. In the three months ended September 30, 2020, MSCI received an immaterial amount in distributions from its equity method investee. The Company’s investment substantially exceeds the Company’s share of the underlying equity of Burgiss. A portion of this excess, representing the excess of the fair value of Burgiss’ intangible assets over their book value, is amortized into “Other expense (income), net” over the useful lives of the respective intangible assets.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent Events	13. SUBSEQUENT EVENTS On October 26, 2020, the Board of Directors declared a quarterly cash dividend of $0.78 per share for the three months ending December 31, 2020 (“fourth quarter 2020”). The fourth quarter 2020 dividend is payable on November 30, 2020 to shareholders of record as of the close of trading on November 13, 2020. Subsequent to the nine months ended September 30, 2020 and through October 23, 2020, the Company repurchased an additional 0.1 million shares of common stock at an average price of $347.26 per share for a total value of $51.0 million.

Introduction and Basis of Pre_2

Introduction and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Use of Estimates	Basis of Presentation and Use of Estimates These unaudited condensed consolidated financial statements include the accounts of MSCI and its wholly owned subsidiaries and include all adjustments of a normal, recurring nature necessary to state fairly the financial condition as of September 30, 2020 and December 31, 2019, the results of operations, comprehensive income and shareholders’ equity (deficit) for the three and nine months ended September 30, 2020 and 2019 and cash flows for the nine months ended September 30, 2020 and 2019. The unaudited condensed consolidated statement of financial condition and related financial statement information as of December 31, 2019 have been derived from the 2019 audited consolidated financial statements but do not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes included in MSCI’s Annual Report on Form 10-K for the year ended December 31, 2019. The results of operations for interim periods are not necessarily indicative of results for the entire year. The Company’s unaudited condensed consolidated financial statements are prepared in accordance with GAAP. These accounting principles require the Company to make certain estimates and judgments that can affect the reported amounts of assets and liabilities as of the date of the unaudited condensed consolidated financial statements, as well as the reported amounts of revenue and expenses during the periods presented. Significant estimates and assumptions made by management include the deferral and recognition of revenue, research and development and software capitalization, assessment of impairment of long-lived assets, accrued compensation, income taxes, incremental borrowing rates and other matters that affect the unaudited condensed consolidated financial statements and related disclosures. The Company believes that estimates used in the preparation of these unaudited condensed consolidated financial statements are reasonable; however, actual results could differ materially from these estimates. Intercompany balances and transactions are eliminated in consolidation.
Concentrations	Concentrations For the nine months ended September 30, 2020 and 2019, BlackRock, Inc. accounted for 10.9% and 11.5% of the Company’s consolidated operating revenues, respectively. For the nine months ended September 30, 2020 and 2019, BlackRock, Inc. accounted for 17.8% and 18.9% of the Index segment operating revenues, respectively. No single customer represented 10.0% or more of operating revenues within the Analytics and All Other segments for the nine months ended September 30, 2020 and 2019.
Allowance for Credit Losses on Accounts Receivable	Allowance for Credit Losses on Accounts Receivable Following the adoption of Accounting Standards Update No. 2016-13, “ Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Changes in the allowance for credit losses on doubtful accounts receivable from December 31, 2018 to September 30, 2020 were as follows: Amount (in Balance as of December 31, 2018 $ 1,027 Addition (reduction) to credit loss expense 1,024 Write-offs, net of recoveries (336 ) Balance as of December 31, 2019 $ 1,715 Addition (reduction) to credit loss expense 1,042 Adjustments and write-offs, net of recoveries (1,434 ) Balance as of September 30, 2020 $ 1,323
Recent Accounting Standards Updates	In June 2016, the FASB issued Accounting Standards Update No. 2016-13, “Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” The FASB issued Accounting Standards Update No. 2018-19 , “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” “Financial Instruments-Credit Losses (Topic 326): Targeted Transition Relief,” “Financial Instruments-Credit Losses (Topic 326): Effective Dates,” “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” The Company adopted ASU 2016-13 and the related clarifications effective January 1, 2020. The adoption did not have a material effect on the Company’s condensed consolidated financial statements. In January 2017, the FASB issued Accounting Standards Update No. 2017-04, “Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment,”

Introduction and Basis of Pre_3

Introduction and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Changes in Allowance for Credit Losses on Doubtful Accounts Receivable	Changes in the allowance for credit losses on doubtful accounts receivable from December 31, 2018 to September 30, 2020 were as follows: Amount (in Balance as of December 31, 2018 $ 1,027 Addition (reduction) to credit loss expense 1,024 Write-offs, net of recoveries (336 ) Balance as of December 31, 2019 $ 1,715 Addition (reduction) to credit loss expense 1,042 Adjustments and write-offs, net of recoveries (1,434 ) Balance as of September 30, 2020 $ 1,323

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2020
Revenue From Contract With Customer [Abstract]
Disaggregation of Revenue	The tables that follow present the disaggregated revenues for the periods indicated: For the Three Months ended September 30, 2020 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 146,387 $ 126,251 $ 40,552 $ 313,190 Asset-based fees 100,371 — — 100,371 Non-recurring 8,933 2,086 753 11,772 Total $ 255,691 $ 128,337 $ 41,305 $ 425,333 For the Nine Months ended September 30, 2020 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 431,631 $ 376,505 $ 119,363 $ 927,499 Asset-based fees 288,642 — — 288,642 Non-recurring 27,582 4,903 3,103 35,588 Total $ 747,855 $ 381,408 $ 122,466 $ 1,251,729 For the Three Months ended September 30, 2019 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 133,403 $ 122,120 $ 32,585 $ 288,108 Asset-based fees 96,013 — — 96,013 Non-recurring 8,011 1,483 636 10,130 Total $ 237,427 $ 123,603 $ 33,221 $ 394,251 For the Nine Months ended September 30, 2019 Segments (in thousands) Index Analytics All Other Total Revenue Types Recurring subscriptions $ 393,222 $ 363,929 $ 102,470 $ 859,621 Asset-based fees 265,554 — — 265,554 Non-recurring 18,974 4,790 2,251 26,015 Total $ 677,750 $ 368,719 $ 104,721 $ 1,151,190
Schedule of Change in Accounts Receivable and Deferred Revenue	The tables that follow present the change in accounts receivable and in deferred revenue between the dates indicated: Accounts receivable Deferred revenue (in thousands) Opening (12/31/2019) $ 499,268 $ 574,656 Closing (09/30/2020) 429,804 531,487 Increase/(decrease) $ (69,464 ) $ (43,169 ) Accounts receivable Deferred revenue (in thousands) Opening (12/31/2018) $ 473,433 $ 537,977 Closing (09/30/2019) 409,519 479,371 Increase/(decrease) $ (63,914 ) $ (58,606 )
Schedule of Remaining Performance Obligations	The remaining performance obligations for contracts that have a duration of greater than one year and the periods in which they are expected to be recognized are as follows: As of September 30, 2020 (in thousands) First 12-month period $ 321,008 Second 12-month period 174,710 Third 12-month period 61,190 Periods thereafter 14,596 Total $ 571,504

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Computation of Basic and Diluted EPS	The following table presents the computation of basic and diluted EPS: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands, except per share data) Net income $ 182,358 $ 136,983 $ 445,606 $ 440,865 Basic weighted average common shares outstanding 83,602 84,765 84,044 84,591 Effect of dilutive securities: Stock options and restricted stock units 877 785 745 942 Diluted weighted average common shares outstanding 84,479 85,550 84,789 85,533 Earnings per basic common share $ 2.18 $ 1.62 $ 5.30 $ 5.21 Earnings per diluted common share $ 2.16 $ 1.60 $ 5.26 $ 5.15

Property, Equipment and Lease_2

Property, Equipment and Leasehold Improvements, Net (Tables)	9 Months Ended
	Sep. 30, 2020
Property Plant And Equipment [Abstract]
Schedule of Property, Equipment and Leasehold Improvements, Net	Property, equipment and leasehold improvements, net consisted of the following as of the specified dates: As of September 30, December 31, 2020 2019 (in thousands) Computer & related equipment $ 184,237 $ 185,794 Furniture & fixtures 14,961 12,478 Leasehold improvements 57,438 52,339 Work-in-process 2,011 8,667 Subtotal 258,647 259,278 Accumulated depreciation and amortization (179,682 ) (168,570 ) Property, equipment and leasehold improvements, net $ 78,965 $ 90,708

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets, Net (Tables)	9 Months Ended
	Sep. 30, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Goodwill by Reportable Segment	The following table presents goodwill by reportable segment: (in thousands) Index Analytics All Other Total Goodwill at December 31, 2019 $ 1,204,694 $ 290,976 $ 67,198 $ 1,562,868 Foreign exchange translation adjustment (805 ) — 314 (491 ) Goodwill at September 30, 2020 $ 1,203,889 $ 290,976 $ 67,512 $ 1,562,377
Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Intangible Assets	The gross carrying and accumulated amortization amounts related to the Company’s intangible assets were as follows: As of September 30, December 31, 2020 2019 (in thousands) Gross intangible assets: Customer relationships $ 356,700 $ 356,700 Trademarks/trade names 207,300 207,300 Technology/software 283,684 263,719 Proprietary data 28,627 28,627 Subtotal 876,311 856,346 Foreign exchange translation adjustment (8,154 ) (7,615 ) Total gross intangible assets $ 868,157 $ 848,731 Accumulated amortization: Customer relationships $ (248,011 ) $ (231,665 ) Trademarks/trade names (140,924 ) (133,305 ) Technology/software (224,928 ) (209,878 ) Proprietary data (15,278 ) (13,963 ) Subtotal (629,141 ) (588,811 ) Foreign exchange translation adjustment 1,842 1,567 Total accumulated amortization $ (627,299 ) $ (587,244 ) Net intangible assets: Customer relationships $ 108,689 $ 125,035 Trademarks/trade names 66,376 73,995 Technology/software 58,756 53,841 Proprietary data 13,349 14,664 Subtotal 247,170 267,535 Foreign exchange translation adjustment (6,312 ) (6,048 ) Total net intangible assets $ 240,858 $ 261,487
Estimated Amortization Expense for Remainder of 2020 and Succeeding Years	The following table presents the estimated amortization expense for the remainder of the year ending December 31, 2020 and succeeding years: Years Ending December 31, Amortization Expense (in thousands) Remainder of 2020 $ 14,995 2021 57,163 2022 49,862 2023 38,955 2024 34,202 Thereafter 45,681 Total $ 240,858

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Schedule of Senior Unsecured Notes	The Company had an aggregate of $3,400.0 million in senior unsecured notes (collectively, the “Senior Notes”) outstanding at September 30, 2020, consisting of five discrete private offerings presented in the table below: Principal Amount Outstanding at Carrying Value at Carrying Value at Fair Value at Fair Value at Maturity Date September 30, 2020 September 30, 2020 December 31, 2019 September 30, 2020 December 31, 2019 (in thousands) Long-term debt 5.25% senior unsecured notes due 2024 November 15, 2024 $ - $ - $ 297,835 $ - $ 309,225 5.75% senior unsecured notes due 2025 August 15, 2025 - - 794,063 - 840,872 4.75% senior unsecured notes due 2026 August 1, 2026 500,000 496,090 495,587 518,330 525,800 5.375% senior unsecured notes due 2027 May 15, 2027 500,000 495,656 495,168 533,490 541,300 4.000% senior unsecured notes due 2029 November 15, 2029 1,000,000 990,091 989,273 1,051,560 1,018,820 3.625% senior unsecured notes due 2030 September 1, 2030 400,000 395,340 - 413,764 - 3.875% senior unsecured notes due 2031 February 15, 2031 1,000,000 988,606 - 1,042,670 - Total long-term debt $ 3,400,000 $ 3,365,783 $ 3,071,926 $ 3,559,814 $ 3,236,017
Schedule of Interest Payments Due Attributable to Senior Notes	Interest payments attributable to the Senior Notes are due as presented in the following table: First semi-annual interest payment date Second semi- annual interest payment date Senior Notes 4.75% senior unsecured notes due 2026 February 1 August 1 5.375% senior unsecured notes due 2027 May 15 November 15 4.000% senior unsecured notes due 2029 May 15 November 15 3.625% senior unsecured notes due 2030 (1) March 1 September 1 3.875% senior unsecured notes due 2031 (2) June 1 December 1 (1) (2) The first payment occurring on December 1, 2020.

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Summary of Future Minimum Commitments Under Operating Leases	Future minimum commitments for the Company’s operating leases in place as of September 30, 2020, the interest and other relevant line items in the Unaudited Condensed Consolidated Statement of Financial Condition are as follows: Maturity of Lease Liabilities Operating (in thousands) Leases Remainder of 2020 $ 5,544 2021 28,598 2022 25,025 2023 23,955 2024 18,651 Thereafter 103,126 Total lease payments $ 204,899 Less: Interest (30,596 ) Present value of lease liabilities $ 174,303 Other accrued liabilities $ 21,491 Long-term operating lease liabilities $ 152,812
Summary of Lease Term and Discount Rate Under Operating Leases	Lease term and discount rate for the Company’s operating leases in place as of September 30, 2020 are as follows: As of September 30, Lease Term and Discount Rate 2020 Weighted-average remaining lease term (years) 9.18 Weighted-average discount rate 3.41 %
Summary of Other Information Under Operating Leases	Other information for the Company’s operating leases in place for the nine months ended September 30, 2020 are as follows: Nine Months Ended Other Information September 30, (in thousands) 2020 Operating cash flows used for operating leases $ 22,735 Leased assets obtained in exchange for new operating lease liabilities $ 7,491

Shareholders' Equity (Deficit)

Shareholders' Equity (Deficit) (Tables)	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Schedule of Company's Common Stock Repurchases Made on Open Market	The following table provides information with respect to repurchases of the Company’s common stock made on the open market: Nine Months Ended Average Price Paid Per Share Total Number of Shares Repurchased Dollar Value of Shares Repurchased (in thousands) September 30, 2020 $ 278.69 2,021 $ 563,336 September 30, 2019 $ 147.97 690 $ 102,081
Schedule of Dividends Declared Per Common Share and Total Amounts Declared, Distributed and Deferred	The following table presents dividends declared per common share as well as total amounts declared, distributed and deferred for the periods indicated: Dividends (in thousands, except per share amounts) Per Share Declared Distributed (Released)/Deferred 2020 Three Months Ended March 31, $ 0.68 $ 59,233 $ 59,455 $ (222 ) Three Months Ended June 30, 0.68 57,360 57,068 292 Three Months Ended September 30, 0.78 65,830 65,454 376 Total $ 2.14 $ 182,423 $ 181,977 $ 446 2019 Three Months Ended March 31, $ 0.58 $ 55,339 $ 57,988 $ (2,649 ) Three Months Ended June 30, 0.58 49,613 49,365 248 Three Months Ended September 30, 0.68 58,176 57,882 294 Total $ 1.84 $ 163,128 $ 165,235 $ (2,107 )
Summary of Activity Related to Shares of Common Stock Issued and Repurchased	The following table presents activity related to shares of common stock issued and repurchased during the nine months ended September 30, 2020: Common Stock Treasury Common Stock Issued Stock Outstanding Balance at December 31, 2019 132,419,412 (47,624,482 ) 84,794,930 Dividend payable/paid 259 (120 ) 139 Common stock issued 377,843 — 377,843 Shares withheld for tax withholding — (153,923 ) (153,923 ) Shares repurchased under stock repurchase programs — (1,309,878 ) (1,309,878 ) Shares issued to directors 21 — 21 Balance at March 31, 2020 132,797,535 (49,088,403 ) 83,709,132 Dividend payable/paid 114 (114 ) — Common stock issued 10,101 — 10,101 Shares withheld for tax withholding — (1,838 ) (1,838 ) Shares repurchased under stock repurchase programs — (113,494 ) (113,494 ) Shares issued to directors 2,229 27,284 29,513 Balance at June 30, 2020 132,809,979 (49,176,565 ) 83,633,414 Dividend payable/paid 54 (54 ) — Common stock issued 13,252 — 13,252 Shares withheld for tax withholding — (6,779 ) (6,779 ) Shares repurchased under stock repurchase programs — (598,031 ) (598,031 ) Shares issued to directors — — — Balance at September 30, 2020 132,823,285 (49,781,429 ) 83,041,856

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Operating Revenue by Reportable Segment	The following table presents operating revenue by reportable segment for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands) Operating revenues Index $ 255,691 $ 237,427 $ 747,855 $ 677,750 Analytics 128,337 123,603 381,408 368,719 All Other 41,305 33,221 122,466 104,721 Total $ 425,333 $ 394,251 $ 1,251,729 $ 1,151,190
Segment Profitability and Reconciliation to Net Income	The following table presents segment profitability and a reconciliation to net income for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands) Index Adjusted EBITDA $ 194,720 $ 177,680 $ 561,563 $ 493,806 Analytics Adjusted EBITDA 45,056 37,797 127,540 113,266 All Other Adjusted EBITDA 9,671 5,312 26,271 23,220 Total operating segment profitability 249,447 220,789 715,374 630,292 2016 Multi-Year PSUs grant payroll tax expense — — — 15,389 Amortization of intangible assets 14,333 12,361 42,171 36,167 Depreciation and amortization of property, equipment and leasehold improvements 7,494 7,209 22,524 22,464 Operating income 227,620 201,219 650,679 556,272 Other expense (income), net 38,577 32,471 159,620 99,487 Provision for income taxes 6,685 31,765 45,453 15,920 Net income $ 182,358 $ 136,983 $ 445,606 $ 440,865
Revenue by Geographic Area	Revenue by geography is based on the shipping address of the ultimate customer utilizing the product. The following table presents revenue by geographic area for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 (in thousands) Operating revenues Americas: United States $ 180,206 $ 177,154 $ 537,071 $ 516,568 Other 18,039 15,878 52,686 48,669 Total Americas 198,245 193,032 589,757 565,237 Europe, the Middle East and Africa ("EMEA"): United Kingdom 65,155 60,856 193,042 174,984 Other 90,539 80,022 268,677 237,745 Total EMEA 155,694 140,878 461,719 412,729 Asia & Australia: Japan 19,885 18,171 59,002 52,838 Other 51,509 42,170 141,251 120,386 Total Asia & Australia 71,394 60,341 200,253 173,224 Total $ 425,333 $ 394,251 $ 1,251,729 $ 1,151,190
Long-Lived Assets by Geographic Area	Long-lived assets consist of property, equipment, leasehold improvements, goodwill and intangible assets, net of accumulated depreciation and amortization. The following table presents long-lived assets by geographic area on the dates indicated: As of September 30, December 31, 2020 2019 (in thousands) Long-lived assets Americas: United States $ 1,754,130 $ 1,781,667 Other 5,026 6,398 Total Americas 1,759,156 1,788,065 EMEA: United Kingdom 77,802 81,338 Other 36,510 36,433 Total EMEA 114,312 117,771 Asia & Australia: Japan 378 398 Other 8,354 8,829 Total Asia & Australia 8,732 9,227 Total $ 1,882,200 $ 1,915,063

Introduction and Basis of Pre_4

Introduction and Basis of Presentation - Additional Information (Detail) - Sales Revenue, Services, Net [Member] - Customer Concentration Risk [Member] - Customer	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Introduction And Basis Of Presentation [Line Items]
Number of major customers represented 10.0% or more of operating revenues	1	1
Blackrock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	10.90%	11.50%
Index [Member] | Blackrock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	17.80%	18.90%
Analytics [Member]
Introduction And Basis Of Presentation [Line Items]
Number of major customers represented 10.0% or more of operating revenues	0	0
All Other [Member]
Introduction And Basis Of Presentation [Line Items]
Number of major customers represented 10.0% or more of operating revenues	0	0

Introduction and Basis of Pre_5

Introduction and Basis of Presentation - Changes in Allowance for Credit Losses on Doubtful Accounts Receivable (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Receivables [Abstract]
Balance at beginning of year	$ 1,715	$ 1,027
Addition (reduction) to credit loss expense	1,042	1,024
Write-offs, net of recoveries		(336)
Adjustments and write-offs, net of recoveries	(1,434)
Balance at ending of year	$ 1,323	$ 1,715

Recent Accounting Standards U_2

Recent Accounting Standards Updates - Additional Information (Details)	Sep. 30, 2020
ASU 2016-13 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adopted	true
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2020
Change in accounting principle, accounting standards update, immaterial effect	true
ASU 2017-04 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adopted	true
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2020

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 425,333	$ 394,251	$ 1,251,729	$ 1,151,190
Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	255,691	237,427	747,855	677,750
Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	128,337	123,603	381,408	368,719
All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	41,305	33,221	122,466	104,721
Recurring Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	313,190	288,108	927,499	859,621
Recurring Subscriptions [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	146,387	133,403	431,631	393,222
Recurring Subscriptions [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	126,251	122,120	376,505	363,929
Recurring Subscriptions [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	40,552	32,585	119,363	102,470
Asset-based Fees [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	100,371	96,013	288,642	265,554
Asset-based Fees [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	100,371	96,013	288,642	265,554
Non-recurring [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	11,772	10,130	35,588	26,015
Non-recurring [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	8,933	8,011	27,582	18,974
Non-recurring [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	2,086	1,483	4,903	4,790
Non-recurring [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 753	$ 636	$ 3,103	$ 2,251

Revenue Recognition - Schedule

Revenue Recognition - Schedule of Change in Accounts Receivable and Deferred Revenue (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Accounts receivable, balance	$ 429,804	$ 409,519	$ 499,268	$ 473,433
Accounts receivable, Increase/(decrease)	(69,464)	(63,914)
Deferred revenue	531,487	479,371	$ 574,656	$ 537,977
Deferred revenue, Increase/(decrease)	$ (43,169)	$ (58,606)

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Revenue From Contract With Customer [Abstract]
Revenue recognized during period included in deferred revenue	$ 494.4	$ 464.3
Revenue, performance obligations and revenue recognition, description	For contracts that have a duration of one year or less, the Company has not disclosed either the remaining performance obligation as of the end of the reporting period or when the Company expects to recognize the revenue.

Revenue Recognition - Schedul_2

Revenue Recognition - Schedule of Remaining Performance Obligations (Detail) $ in Thousands	Sep. 30, 2020USD ($)
Revenue Recognition [Line Items]
Remaining performance obligations	$ 571,504
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	321,008
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	174,710
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	61,190
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 14,596

Revenue Recognition - Schedul_3

Revenue Recognition - Schedule of Remaining Performance Obligations (Detail 1) $ in Thousands	Sep. 30, 2020USD ($)
Revenue From Contract With Customer [Abstract]
Remaining performance obligations	$ 571,504

Revenue Recognition - Schedul_4

Revenue Recognition - Schedule of Remaining Performance Obligations (Parenthetical) (Detail)	Sep. 30, 2020
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-10-01
Revenue Recognition [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Recognition [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-10-01
Revenue Recognition [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-10-01
Revenue Recognition [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period

Earnings Per Common Share - Com

Earnings Per Common Share - Computation of Basic and Diluted EPS (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Net income	$ 182,358	$ 115,123	$ 148,125	$ 136,983	$ 125,690	$ 178,192	$ 445,606	$ 440,865
Basic weighted average common shares outstanding	83,602			84,765			84,044	84,591
Effect of dilutive securities:
Stock options and restricted stock units	877			785			745	942
Diluted weighted average common shares outstanding	84,479			85,550			84,789	85,533
Earnings per basic common share	$ 2.18			$ 1.62			$ 5.30	$ 5.21
Earnings per diluted common share	$ 2.16			$ 1.60			$ 5.26	$ 5.15

Property, Equipment and Lease_3

Property, Equipment and Leasehold Improvements, Net - Schedule of Property, Equipment and Leasehold Improvements, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Abstract]
Computer & related equipment	$ 184,237	$ 185,794
Furniture & fixtures	14,961	12,478
Leasehold improvements	57,438	52,339
Work-in-process	2,011	8,667
Subtotal	258,647	259,278
Accumulated depreciation and amortization	(179,682)	(168,570)
Property, equipment and leasehold improvements, net	$ 78,965	$ 90,708

Property, Equipment and Lease_4

Property, Equipment and Leasehold Improvements, Net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Property Plant And Equipment [Abstract]
Depreciation and amortization of property, equipment and leasehold improvements	$ 7,494	$ 7,209	$ 22,524	$ 22,464

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets, Net - Schedule of Goodwill by Reportable Segment (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Goodwill [Line Items]
Goodwill, Beginning balance	$ 1,562,868
Foreign exchange translation adjustment	(491)
Goodwill, Ending balance	1,562,377
Index [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	1,204,694
Foreign exchange translation adjustment	(805)
Goodwill, Ending balance	1,203,889
Analytics [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	290,976
Goodwill, Ending balance	290,976
All Other [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	67,198
Foreign exchange translation adjustment	314
Goodwill, Ending balance	$ 67,512

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets, Net - Additional Information (Detail)	Jul. 01, 2020USD ($)Segment	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)
Goodwill [Line Items]
Number of operating segments tested for qualitative impairment | Segment	4
Impairment of goodwill	$ 0
Amortization of intangible assets		$ 14,333,000	$ 12,361,000	$ 42,171,000	$ 36,167,000
Acquired Intangible Assets [Member]
Goodwill [Line Items]
Amortization of intangible assets		8,300,000	8,600,000	25,700,000	26,000,000
Capitalized Software [Member]
Goodwill [Line Items]
Amortization of intangible assets		$ 6,000,000	$ 3,800,000	$ 16,500,000	$ 10,200,000

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets, Net - Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	$ 876,311	$ 856,346
Foreign exchange translation adjustment	(8,154)	(7,615)
Gross carrying value	868,157	848,731
Accumulated amortization excluding foreign exchange translation adjustment	(629,141)	(588,811)
Foreign exchange translation adjustment	1,842	1,567
Accumulated amortization	(627,299)	(587,244)
Net carrying value excluding foreign exchange translation adjustment	247,170	267,535
Foreign exchange translation adjustment	(6,312)	(6,048)
Net carrying value	240,858	261,487
Customer Relationships [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	356,700	356,700
Accumulated amortization excluding foreign exchange translation adjustment	(248,011)	(231,665)
Net carrying value excluding foreign exchange translation adjustment	108,689	125,035
Trademarks/Trade Names [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	207,300	207,300
Accumulated amortization excluding foreign exchange translation adjustment	(140,924)	(133,305)
Net carrying value excluding foreign exchange translation adjustment	66,376	73,995
Technology/Software [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	283,684	263,719
Accumulated amortization excluding foreign exchange translation adjustment	(224,928)	(209,878)
Net carrying value excluding foreign exchange translation adjustment	58,756	53,841
Proprietary Data [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	28,627	28,627
Accumulated amortization excluding foreign exchange translation adjustment	(15,278)	(13,963)
Net carrying value excluding foreign exchange translation adjustment	$ 13,349	$ 14,664

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets, Net - Estimated Amortization Expense for Remainder of 2020 and Succeeding Years (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Remainder of 2020	$ 14,995
2021	57,163
2022	49,862
2023	38,955
2024	34,202
Thereafter	45,681
Net carrying value	$ 240,858	$ 261,487

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	Nov. 15, 2019	May 15, 2018	Aug. 04, 2016	Sep. 30, 2020	May 26, 2020	Mar. 04, 2020	Nov. 20, 2014
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 3,400,000,000
Loss on extinguishment of debt				44,930,000
Prepaid and Other Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				500,000
Other Non-Current Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				1,400,000
Long-term Debt [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				$ 34,200,000
Revolving Credit Agreement [Member]
Schedule Of Commitments And Contingencies [Line Items]
Revolving credit facility, maximum borrowing	$ 400,000,000	$ 250,000,000	$ 220,000,000				$ 200,000,000
Revolving credit agreement, term				5 years
Revolving credit agreement, extended term	1 year	1 year	1 year
4.75% Senior Unsecured Notes Due 2026 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 500,000,000
Debt instrument interest rate				4.75%
Maturity date				Aug. 1, 2026
Redemption description				At any time prior to August 1, 2021, the Company may redeem all or part of the 2026 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
5.375% Senior Unsecured Notes Due 2027 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 500,000,000
Debt instrument interest rate				5.375%
Maturity date				May 15, 2027
Redemption description				At any time prior to May 15, 2022, the Company may redeem all or part of the 2027 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
Percentage of aggregate principal amount redeemed				35.00%
Redemption price				105.375%
4.000% Senior Unsecured Notes Due 2029 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 1,000,000,000
Debt instrument interest rate				4.00%
Maturity date				Nov. 15, 2029
Redemption description				At any time prior to November 15, 2024, the Company may redeem all or part of the 2029 Senior Notes at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
Percentage of aggregate principal amount redeemed				35.00%
Redemption price				104.00%
3.625% Senior Unsecured Notes Due 2030 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 400,000,000		$ 400,000,000
Debt instrument interest rate				3.625%		3.625%
Maturity date				Sep. 1, 2030
Redemption description				At any time prior to March 1, 2025, the Company may redeem all or part of the 2030 Senior Notes at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
Redemption price				103.625%
3.625% Senior Unsecured Notes Due 2030 [Member] | Maximum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Percentage of aggregate principal amount redeemed				35.00%
5.25% Senior Unsecured Notes Due 2024 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount						$ 300,000,000
Debt instrument interest rate				5.25%		5.25%
Maturity date				Nov. 15, 2024
5.25% Senior Unsecured Notes Due 2024 [Member] | Other expense (income) [Member]
Schedule Of Commitments And Contingencies [Line Items]
Loss on extinguishment of debt				$ 10,000,000
Write-off of unamortized debt issuance costs				2,100,000
5.25% Senior Unsecured Notes Due 2024 [Member] | Other expense (income) [Member] | Indenture [Member]
Schedule Of Commitments And Contingencies [Line Items]
Loss on debt extinguishment includes applicable premium and redemption price				7,900,000
3.875% Senior Unsecured Notes Due 2031 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 1,000,000,000	$ 1,000,000,000
Debt instrument interest rate				3.875%	3.875%
Maturity date				Feb. 15, 2031
Redemption description				At any time prior to June 1, 2025, the Company may redeem all or part of the 2031 Senior Notes at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest, if any, to, but excluding, the redemption date.
Percentage of aggregate principal amount redeemed				50.00%
Redemption price				103.875%
3.875% Senior Unsecured Notes Due 2031 [Member] | Maximum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Percentage of aggregate principal amount redeemed				35.00%
5.75% Senior Unsecured Notes Due 2025 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount					$ 800,000,000
Debt instrument interest rate				5.75%	5.75%
Maturity date				Aug. 15, 2025
5.75% Senior Unsecured Notes Due 2025 [Member] | Other expense (income) [Member]
Schedule Of Commitments And Contingencies [Line Items]
Loss on extinguishment of debt				$ 35,000,000
Write-off of unamortized debt issuance costs				5,500,000
5.75% Senior Unsecured Notes Due 2025 [Member] | Other expense (income) [Member] | Indenture [Member]
Schedule Of Commitments And Contingencies [Line Items]
Loss on debt extinguishment includes applicable premium and redemption price				29,500,000
Senior Unsecured Notes [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				3,400,000,000
Senior Notes and Revolving Credit Facility [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				$ 36,100,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Senior Unsecured Notes (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2020	May 26, 2020	Mar. 04, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal Amount Outstanding	$ 3,400,000,000
Carrying Value	3,365,783,000			$ 3,071,926,000
Fair Value	$ 3,559,814,000			3,236,017,000
5.25% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Maturity Date	Nov. 15, 2024
Principal Amount Outstanding			$ 300,000,000
Carrying Value				297,835,000
Fair Value				309,225,000
5.75% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Maturity Date	Aug. 15, 2025
Principal Amount Outstanding		$ 800,000,000
Carrying Value				794,063,000
Fair Value				840,872,000
4.75% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Maturity Date	Aug. 1, 2026
Principal Amount Outstanding	$ 500,000,000
Carrying Value	496,090,000			495,587,000
Fair Value	$ 518,330,000			525,800,000
5.375% Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
Maturity Date	May 15, 2027
Principal Amount Outstanding	$ 500,000,000
Carrying Value	495,656,000			495,168,000
Fair Value	$ 533,490,000			541,300,000
4.000% Senior Unsecured Notes Due 2029 [Member]
Debt Instrument [Line Items]
Maturity Date	Nov. 15, 2029
Principal Amount Outstanding	$ 1,000,000,000
Carrying Value	990,091,000			989,273,000
Fair Value	$ 1,051,560,000			$ 1,018,820,000
3.625% Senior Unsecured Notes Due 2030 [Member]
Debt Instrument [Line Items]
Maturity Date	Sep. 1, 2030
Principal Amount Outstanding	$ 400,000,000		$ 400,000,000
Carrying Value	395,340,000
Fair Value	$ 413,764,000
3.875% Senior Unsecured Notes Due 2031 [Member]
Debt Instrument [Line Items]
Maturity Date	Feb. 15, 2031
Principal Amount Outstanding	$ 1,000,000,000	$ 1,000,000,000
Carrying Value	988,606,000
Fair Value	$ 1,042,670,000

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Senior Unsecured Notes (Parenthetical) (Detail)	Sep. 30, 2020	May 26, 2020	Mar. 04, 2020
5.25% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.25%		5.25%
5.75% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.75%	5.75%
4.75% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.75%
5.375% Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.375%
4.000% Senior Unsecured Notes Due 2029 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.00%
3.625% Senior Unsecured Notes Due 2030 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.625%		3.625%
3.875% Senior Unsecured Notes Due 2031 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	3.875%	3.875%

Commitments and Contingencies_4

Commitments and Contingencies - Schedule of Interest Payments Due Attributable to Senior Notes (Detail)	9 Months Ended
	Sep. 30, 2020
4.75% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
First semi-annual interest payment date	--02-01
Second semi-annual interest payment date	--08-01
5.375% Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
First semi-annual interest payment date	--05-15
Second semi-annual interest payment date	--11-15
4.000% Senior Unsecured Notes Due 2029 [Member]
Debt Instrument [Line Items]
First semi-annual interest payment date	--05-15
Second semi-annual interest payment date	--11-15
3.625% Senior Unsecured Notes Due 2030 [Member]
Debt Instrument [Line Items]
First semi-annual interest payment date	--03-01
Second semi-annual interest payment date	--09-01
3.875% Senior Unsecured Notes Due 2031 [Member]
Debt Instrument [Line Items]
First semi-annual interest payment date	--06-01
Second semi-annual interest payment date	--12-01

Commitments and Contingencies_5

Commitments and Contingencies - Schedule of Interest Payments Due Attributable to Senior Notes (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2020
3.625% Senior Unsecured Notes Due 2030 [Member]
Debt Instrument [Line Items]
First payment occurring date	Sep. 1, 2020
3.875% Senior Unsecured Notes Due 2031 [Member]
Debt Instrument [Line Items]
First payment occurring date	Dec. 1, 2020

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Leases [Abstract]
Operating lease, expense	$ 7.5	$ 7.2	$ 25.4	$ 21.7

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Commitments Under Operating Leases (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Maturity of Lease Liabilities
Remainder of 2020	$ 5,544
2021	28,598
2022	25,025
2023	23,955
2024	18,651
Thereafter	103,126
Total lease payments	204,899
Less: Interest	(30,596)
Present value of lease liabilities	174,303
Other accrued liabilities	$ 21,491
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherAccruedLiabilitiesCurrent
Long-term operating lease liabilities	$ 152,812	$ 164,144

Leases - Summary of Lease Term

Leases - Summary of Lease Term and Discount Rate Under Operating Lease (Detail)	Sep. 30, 2020
Leases [Abstract]
Weighted-average remaining lease term (years)	9 years 2 months 4 days
Weighted-average discount rate	3.41%

Leases - Summary of Other Infor

Leases - Summary of Other Information Under Operating Lease (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Leases [Abstract]
Operating cash flows used for operating leases	$ 22,735
Leased assets obtained in exchange for new operating lease liabilities	$ 7,491

Shareholders' Equity (Deficit_2

Shareholders' Equity (Deficit) - Additional Information (Detail) - USD ($)	Sep. 30, 2020	Oct. 29, 2019	May 01, 2018	Oct. 26, 2016
2016 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase program authorizing the purchase of shares				$ 750,000,000
Stock repurchase program, remaining authorized repurchase amount			$ 523,100,000
2018 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase program authorizing the purchase of shares			$ 1,000,000,000
Stock repurchase program, remaining authorized repurchase amount		$ 706,100,000
2019 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase program authorizing the purchase of shares		750,000,000
Stock repurchase program, remaining authorized repurchase amount	$ 892,800,000	$ 1,456,100,000

Shareholders' Equity (Deficit_3

Shareholders' Equity (Deficit) - Schedule of Company's Common Stock Repurchases Made on Open Market (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Dollar Value of Shares Repurchased	$ 206,566	$ 31,071	$ 325,699	$ 102,081
Open Market Purchases of Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Average Price Paid Per Share					$ 278.69	$ 147.97
Total Number of Shares Repurchased					2,021	690
Dollar Value of Shares Repurchased					$ 563,336	$ 102,081

Shareholders' Equity (Deficit_4

Shareholders' Equity (Deficit) - Schedule of Dividends Declared Per Common Share and Total Amounts Declared, Distributed and Deferred (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement Of Stockholders Equity [Abstract]
Dividend declared per common share	$ 0.78	$ 0.68	$ 0.68	$ 0.68	$ 0.58	$ 0.58	$ 2.14	$ 1.84
Cash dividends declared, Amount	$ 65,830	$ 57,360	$ 59,233	$ 58,176	$ 49,613	$ 55,339	$ 182,423	$ 163,128
Cash dividends distributed, Amount	65,454	57,068	59,455	57,882	49,365	57,988	181,977	165,235
Cash dividends (released)/deferred, Amount	$ 376	$ 292	$ (222)	$ 294	$ 248	$ (2,649)	$ 446	$ (2,107)

Shareholders' Equity (Deficit_5

Shareholders' Equity (Deficit) - Summary of Activity Related to Shares of Common Stock Issued and Repurchased (Detail) - shares	3 Months Ended			9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2020
Common Stock Issued [Member]
Common Stock Outstanding [Line Items]
Beginning balance	132,809,979	132,797,535	132,419,412	132,419,412
Dividend payable/paid	54	114	259
Common stock issued	13,252	10,101	377,843
Shares issued to directors		2,229	21
Ending balance	132,823,285	132,809,979	132,797,535	132,823,285
Treasury Stock [Member]
Common Stock Outstanding [Line Items]
Beginning balance	(49,176,565)	(49,088,403)	(47,624,482)	(47,624,482)
Dividend payable/paid	(54)	(114)	(120)
Shares withheld for tax withholding	(6,779)	(1,838)	(153,923)
Shares repurchased under stock repurchase programs	(598,031)	(113,494)	(1,309,878)
Shares issued to directors		27,284
Ending balance	(49,781,429)	(49,176,565)	(49,088,403)	(49,781,429)
Common Stock Outstanding [Member]
Common Stock Outstanding [Line Items]
Beginning balance	83,633,414	83,709,132	84,794,930	84,794,930
Dividend payable/paid			139
Common stock issued	13,252	10,101	377,843
Shares withheld for tax withholding	(6,779)	(1,838)	(153,923)
Shares repurchased under stock repurchase programs	(598,031)	(113,494)	(1,309,878)
Shares issued to directors		29,513	21
Ending balance	83,041,856	83,633,414	83,709,132	83,041,856

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Examination [Line Items]
Provision for income taxes	$ 6,685	$ 31,765	$ 45,453	$ 15,920
Effective tax rate			9.30%	3.50%
Amounts effect on effective tax rate	61,700	$ 82,700	$ 61,700	$ 82,700
Tax favorable impact on prior years of final regulations	$ 20,800
Tax Impact of loss on debt extinguishment			11,500
Benefit related to revaluation of cost of deemed repatriation of foreign earnings			6,300
Decrease in unrecognized tax benefit			$ 9,600
Minimum [Member]
Income Tax Examination [Line Items]
Tax years under examination			2007
Maximum [Member]
Income Tax Examination [Line Items]
Tax years under examination			2019
2016 Multi-Year PSUs [Member] | Restricted Stock Units [Member]
Income Tax Examination [Line Items]
Amount of excess tax benefits recognized on the conversion				66,600
Accounting Standards Update 2016-09 [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member]
Income Tax Examination [Line Items]
Amount of excess tax benefits recognized on the conversion			$ 21,900	$ 10,800

Segment Information - Additiona

Segment Information - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2020Segment
Segment Reporting [Abstract]
Number of operating segments	5

Segment Information - Operating

Segment Information - Operating Revenue by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 425,333	$ 394,251	$ 1,251,729	$ 1,151,190
Index [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	255,691	237,427	747,855	677,750
Analytics [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	128,337	123,603	381,408	368,719
All Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 41,305	$ 33,221	$ 122,466	$ 104,721

Segment Information - Segment P

Segment Information - Segment Profitability and Reconciliation to Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 249,447			$ 220,789			$ 715,374	$ 630,292
2016 Multi-Year PSUs grant payroll tax expense								15,389
Amortization of intangible assets	14,333			12,361			42,171	36,167
Depreciation and amortization of property, equipment and leasehold improvements	7,494			7,209			22,524	22,464
Operating income	227,620			201,219			650,679	556,272
Other expense (income), net	38,577			32,471			159,620	99,487
Provision for income taxes	6,685			31,765			45,453	15,920
Net income	182,358	$ 115,123	$ 148,125	136,983	$ 125,690	$ 178,192	445,606	440,865
Index [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	194,720			177,680			561,563	493,806
Analytics [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	45,056			37,797			127,540	113,266
All Other [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 9,671			$ 5,312			$ 26,271	$ 23,220

Segment Information - Revenue b

Segment Information - Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 425,333	$ 394,251	$ 1,251,729	$ 1,151,190
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	180,206	177,154	537,071	516,568
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	18,039	15,878	52,686	48,669
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	198,245	193,032	589,757	565,237
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	65,155	60,856	193,042	174,984
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	90,539	80,022	268,677	237,745
Europe, the Middle East and Africa ("EMEA") [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	155,694	140,878	461,719	412,729
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	19,885	18,171	59,002	52,838
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	51,509	42,170	141,251	120,386
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 71,394	$ 60,341	$ 200,253	$ 173,224

Segment Information - Long-Live

Segment Information - Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1,882,200	$ 1,915,063
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,754,130	1,781,667
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	5,026	6,398
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,759,156	1,788,065
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	77,802	81,338
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	36,510	36,433
Total EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	114,312	117,771
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	378	398
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	8,354	8,829
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 8,732	$ 9,227

Equity Method Investment - Addi

Equity Method Investment - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Jan. 31, 2020	Sep. 30, 2020
Schedule Of Equity Method Investments [Line Items]
Acquisition of equity method investment including capitalized costs		$ 190,816
The Burgiss Group, LLC [Member]
Schedule Of Equity Method Investments [Line Items]
Acquisition of equity method investment including capitalized costs	$ 190,800
Equity method investment, non controlling interest percentage	40.00%

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	Oct. 26, 2020	Oct. 23, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Subsequent Event [Line Items]
Dividend declared per common share			$ 0.78	$ 0.68	$ 0.68	$ 0.68	$ 0.58	$ 0.58	$ 2.14	$ 1.84
Common stock repurchased, value			$ 206,566	$ 31,071	$ 325,699			$ 102,081
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend declared per common share	$ 0.78
Quarterly dividend declared date	Oct. 26, 2020
Quarterly dividend payable date	Nov. 30, 2020
Quarterly dividend record date	Nov. 13, 2020
Common stock repurchased, shares		0.1
Average price paid per share		$ 347.26
Common stock repurchased, value		$ 51,000