MSCI (MSCI) 10-Q 31 Oct 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 25, 2019
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
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		84,707,270
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, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 881,150	$ 904,176
Accounts receivable (net of allowances of $1,485 and $1,027 at September 30, 2019 and December 31, 2018, respectively)	409,519	473,433
Prepaid income taxes	55,020	19,273
Prepaid and other assets	40,399	38,207
Total current assets	1,386,088	1,435,089
Property, equipment and leasehold improvements, net	86,415	90,877
Right of use assets	164,942
Goodwill	1,544,078	1,545,761
Intangible assets, net	261,942	280,803
Deferred tax assets	16,584	14,903
Other non-current assets	19,693	20,519
Total assets	3,479,742	3,387,952
Current liabilities:
Accounts payable	2,396	3,892
Income taxes payable	11,654	16,253
Accrued compensation and related benefits	122,642	137,045
Other accrued liabilities	128,458	113,841
Deferred revenue	479,371	537,977
Total current liabilities	744,521	809,008
Long-term debt	2,578,159	2,575,502
Long-term operating lease liabilities	163,567
Deferred tax liabilities	72,960	82,008
Other non-current liabilities	68,391	87,928
Total liabilities	3,627,598	3,554,446
Commitments and Contingencies (see Note 7 and Note 9)
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; 132,309,213 and 130,029,926 common shares issued and 84,707,245 and 84,174,138 common shares outstanding at September 30, 2019 and December 31, 2018, respectively)	1,323	1,300
Treasury shares, at cost (47,601,968 and 45,855,788 common shares held at September 30, 2019 and December 31, 2018, respectively)	(3,559,963)	(3,272,774)
Additional paid in capital	1,338,194	1,306,428
Retained earnings	2,134,688	1,856,951
Accumulated other comprehensive loss	(62,098)	(58,399)
Total shareholders' equity (deficit)	(147,856)	(166,494)
Total liabilities and shareholders' equity (deficit)	$ 3,479,742	$ 3,387,952

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 1,485	$ 1,027
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	132,309,213	130,029,926
Common stock, shares outstanding	84,707,245	84,174,138
Treasury shares	47,601,968	45,855,788

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Operating revenues	$ 394,251	$ 357,934	$ 1,151,190	$ 1,072,296
Operating expenses:
Cost of revenues	70,486	70,906	224,807	213,578
Selling and marketing	52,107	46,149	159,812	139,974
Research and development	24,310	20,591	71,234	61,099
General and administrative	26,559	24,751	80,434	74,974
Amortization of intangible assets	12,361	11,681	36,167	42,556
Depreciation and amortization of property, equipment and leasehold improvements	7,209	7,453	22,464	23,035
Total operating expenses	193,032	181,531	594,918	555,216
Operating income	201,219	176,403	556,272	517,080
Interest income	(3,673)	(6,522)	(11,104)	(13,573)
Interest expense	35,922	35,902	107,752	97,223
Other expense (income)	222	177	2,839	(9,177)
Other expense (income), net	32,471	29,557	99,487	74,473
Income before provision for income taxes	168,748	146,846	456,785	442,607
Provision for income taxes	31,765	23,014	15,920	86,854
Net income	$ 136,983	$ 123,832	$ 440,865	$ 355,753
Earnings per basic common share	$ 1.62	$ 1.39	$ 5.21	$ 3.98
Earnings per diluted common share	$ 1.60	$ 1.36	$ 5.15	$ 3.87
Weighted average shares outstanding used in computing earnings per share
Basic	84,765	88,796	84,591	89,323
Diluted	85,550	91,372	85,533	91,843

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 136,983	$ 123,832	$ 440,865	$ 355,753
Other comprehensive (loss) income:
Foreign currency translation adjustments	(5,533)	(3,338)	(4,853)	(11,860)
Income tax effect	1,124		1,085
Foreign currency translation adjustments, net	(4,409)	(3,338)	(3,768)	(11,860)
Pension and other post-retirement adjustments	134	22	103	116
Income tax effect	(64)	(10)	(34)	(55)
Pension and other post-retirement adjustments, net	70	12	69	61
Net investment hedge adjustments				1,937
Net investment hedge adjustments, net				1,937
Other comprehensive (loss) income, net of tax	(4,339)	(3,326)	(3,699)	(9,862)
Comprehensive income	$ 132,644	$ 120,506	$ 437,166	$ 345,891

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2017	$ 401,012	$ 1,295	$ (2,321,989)	$ 1,264,849	$ 1,505,204	$ (48,347)
Net income	115,092				115,092
ASC 606 Retained Earnings Adjustment | Accounting Standards Update 2014-09	16,135				16,135
Dividends	(34,848)				(34,848)
Dividends paid in shares	35			35
Other comprehensive income (loss), net of tax	4,012					4,012
Common stock issued	5	5
Shares withheld for tax withholding and exercises	(22,932)		(22,932)
Compensation payable in common stock and options	11,123			11,123
Common stock repurchased and held in treasury	(68,345)		(68,345)
Common stock issued to directors and held in treasury	(17)		(17)
Exercise of stock options	102			102
Balance at Mar. 31, 2018	421,374	1,300	(2,413,283)	1,276,109	1,601,583	(44,335)
Balance at Dec. 31, 2017	401,012	1,295	(2,321,989)	1,264,849	1,505,204	(48,347)
Net income	355,753
Dividends	(121,365)
Balance at Sep. 30, 2018	378,441	1,300	(2,615,827)	1,295,450	1,755,727	(58,209)
Balance at Mar. 31, 2018	421,374	1,300	(2,413,283)	1,276,109	1,601,583	(44,335)
Net income	116,829				116,829
Dividends	(34,254)				(34,254)
Dividends paid in shares	19			19
Other comprehensive income (loss), net of tax	(10,548)					(10,548)
Shares withheld for tax withholding and exercises	(481)		(481)
Compensation payable in common stock and options	9,229			9,229
Common stock repurchased and held in treasury	(154,898)		(154,898)
Common stock issued to directors and held in treasury	(866)		(866)
Exercise of stock options	18			18
Balance at Jun. 30, 2018	346,422	1,300	(2,569,528)	1,285,375	1,684,158	(54,883)
Net income	123,832				123,832
Dividends	(52,263)				(52,263)
Dividends paid in shares	29			29
Other comprehensive income (loss), net of tax	(3,326)					(3,326)
Shares withheld for tax withholding and exercises	(664)		(664)
Compensation payable in common stock and options	9,801			9,801
Common stock repurchased and held in treasury	(45,606)		(45,606)
Common stock issued to directors and held in treasury	(29)		(29)
Exercise of stock options	245			245
Balance at Sep. 30, 2018	378,441	1,300	(2,615,827)	1,295,450	1,755,727	(58,209)
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 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 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 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)

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Shareholders' Equity (Deficit) (Parenthetical) - $ / shares	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Stockholders Equity [Abstract]
Dividends per common share	$ 0.68	$ 0.58	$ 0.58	$ 0.58	$ 0.38	$ 0.38	$ 1.84	$ 1.34

Condensed Consolidated Statem_7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities
Net income	$ 440,865	$ 355,753
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	36,167	42,556
Stock-based compensation expense	30,485	27,942
Depreciation and amortization of property, equipment and leasehold improvements	22,464	23,035
Non-cash operating lease expense	16,778
Amortization of debt origination fees	2,956	2,730
Deferred taxes	(9,844)	(9,110)
Gain on divestitures, net of costs		(12,055)
Other non-cash adjustments	708	357
Changes in assets and liabilities:
Accounts receivable	62,331	(60,250)
Prepaid income taxes	(37,199)	(6,229)
Prepaid and other assets	(3,965)	(3,756)
Accounts payable	(1,482)	605
Accrued compensation and related benefits	(14,107)	(18,806)
Income taxes payable	(4,251)	(9,562)
Other accrued liabilities	(6,795)	21,157
Deferred revenue	(57,804)	89,730
Long-term operating lease liabilities	(14,774)
Other	3,347	(4,510)
Net cash provided by operating activities	465,880	439,587
Cash flows from investing activities
Capital expenditures	(17,216)	(13,069)
Capitalized software development costs	(18,086)	(13,115)
Proceeds from divestitures		21,010
Proceeds from the sale of capital equipment	10	10
Net cash used in investing activities	(35,292)	(5,164)
Cash flows from financing activities
Proceeds from exercise of stock options	1,052	365
Repurchase of treasury shares	(286,290)	(292,970)
Proceeds from borrowings		500,000
Payment of debt issuance costs		(6,262)
Payment of dividends	(165,077)	(120,533)
Net cash (used in) provided by financing activities	(450,315)	80,600
Effect of exchange rate changes	(3,299)	(6,127)
Net (decrease) increase in cash	(23,026)	508,896
Cash and cash equivalent, beginning of period	904,176	889,502
Cash and cash equivalent, end of period	881,150	1,398,398
Supplemental disclosure of cash flow information:
Cash paid for interest	105,015	91,503
Cash paid for income taxes	65,364	110,197
Supplemental disclosure of non-cash investing activities
Property, equipment and leasehold improvements accrued, but not yet paid	4,189	3,777
Supplemental disclosure of non-cash financing activities
Cash dividends declared, but not yet paid	$ 778	$ 889

Introduction and Basis of Prese

Introduction and Basis of Presentation	9 Months Ended
	Sep. 30, 2019
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 investment decision support tools and services for the global investment community. MSCI is dynamic and flexible in the delivery of content and capabilities, such as 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 subsidiaries and include all adjustments of a normal, recurring nature necessary to state fairly the financial condition as of September 30, 2019 and December 31, 2018, the results of operations, comprehensive income and shareholders’ equity (deficit) for the three and nine months ended September 30, 2019 and 2018 and cash flows for the nine months ended September 30, 2019 and 2018. The unaudited condensed consolidated statement of financial condition and related financial statement information as of December 31, 2018 have been derived from the 2018 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, 2018. 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, 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, 2019 and 2018, BlackRock, Inc. accounted for 11.5% and 12.2% of the Company’s consolidated operating revenues, respectively. For the nine months ended September 30, 2019 and 2018, BlackRock, Inc. accounted for 18.9% and 20.7% 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, 2019 and 2018.

Recent Accounting Standards Upd

Recent Accounting Standards Updates	9 Months Ended
	Sep. 30, 2019
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Standards Updates	2. RECENT ACCOUNTING STANDARDS UPDATES In February 2016, the FASB issued Accounting Standards Update No. 2016-02, “ Leases (Topic 842) In July 2018, the FASB issued Accounting Standards Update No. 2018-10, “Codification Improvements to Topic 842, Leases,” “Targeted Improvements,” The Company adopted ASU 2016-02 effective January 1, 2019 using the optional transition method available under ASU 2018-11. In preparation for adoption of the guidance, the Company implemented internal controls and processes to enable the preparation of financial information. MSCI elected to apply the transition package of practical expedients permitted within the new guidance which, among other things, allowed the Company to carry forward the historical lease classification. In addition, MSCI elected the hindsight practical expedient to determine the reasonably certain lease term for existing leases. The Company made an election to apply the exemption allowed under ASU 2016-02 for leases with an initial term of 12 months or less to not be recorded in the Condensed Consolidated Statement of Financial Condition and to only recognize the related amounts in the Condensed Consolidated Statement of Income on a straight-line basis over the lease term. See Note 8, “Leases” of the Notes to the Unaudited Condensed Consolidated Financial Statements included herein for further information regarding leases. In August 2018, the FASB issued Accounting Standards Update No. 2018-15, “ Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract,

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2019
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 groups its revenues by segment. The tables that follow present the disaggregated revenues for the periods indicated (in thousands): For the Three Months ended September 30, 2019 Segments 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 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 For the Three Months ended September 30, 2018 Segments Index Analytics All Other Total Revenue Types Recurring subscriptions $ 121,285 $ 118,857 $ 27,234 $ 267,376 Asset-based fees 82,007 — — 82,007 Non-recurring 6,902 1,041 608 8,551 Total $ 210,194 $ 119,898 $ 27,842 $ 357,934 For the Nine Months ended September 30, 2018 Segments Index Analytics All Other Total Revenue Types Recurring subscriptions $ 354,116 $ 354,629 $ 86,185 $ 794,930 Asset-based fees 255,126 — — 255,126 Non-recurring 15,800 3,375 3,065 22,240 Total $ 625,042 $ 358,004 $ 89,250 $ 1,072,296 The table that follows presents the change in accounts receivable and in deferred revenue between the dates indicated (in thousands): Accounts receivable Deferred revenue Opening (12/31/2018) $ 473,433 $ 537,977 Closing (09/30/2019) 409,519 479,371 Increase/(decrease) $ (63,914 ) $ (58,606 ) The amount of revenue recognized in the period that was included in the opening current deferred revenue, which reflects contract liability amounts, was $464.3 million. 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, 2019, 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, 2019 (in thousands) First 12-month period $ 301,420 Second 12-month period 167,628 Third 12-month period 61,866 Periods thereafter 24,577 Total $ 555,491

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2019
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. There were an immaterial number of anti-dilutive securities excluded from the calculation of diluted EPS for all periods presented. The following table presents the computation of basic and diluted EPS: Three Months Ended Nine Months Ended September 30, September 30, 2019 2018 2019 2018 (in thousands, except per share data) Net income $ 136,983 $ 123,832 $ 440,865 $ 355,753 Basic weighted average common shares outstanding 84,765 88,796 84,591 89,323 Effect of dilutive securities: Stock options and restricted stock units 785 2,576 942 2,520 Diluted weighted average common shares outstanding 85,550 91,372 85,533 91,843 Earnings per basic common share $ 1.62 $ 1.39 $ 5.21 $ 3.98 Earnings per diluted common share $ 1.60 $ 1.36 $ 5.15 $ 3.87

Property, Equipment and Leaseho

Property, Equipment and Leasehold Improvements, Net	9 Months Ended
	Sep. 30, 2019
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, 2019 2018 (in thousands) Computer & related equipment $ 172,811 $ 200,414 Furniture & fixtures 12,157 12,033 Leasehold improvements 51,695 53,429 Work-in-process 9,823 10,506 Subtotal 246,486 276,382 Accumulated depreciation and amortization (160,071 ) (185,505 ) Property, equipment and leasehold improvements, net $ 86,415 $ 90,877 Depreciation and amortization expense of property, equipment and leasehold improvements was $7.2 million and $7.5 million for the three months ended September 30, 2019 and 2018, respectively. Depreciation and amortization expense of property, equipment and leasehold improvements was $22.5 million and $23.0 million for the nine months ended September 30, 2019 and 2018, respectively.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, Net	9 Months Ended
	Sep. 30, 2019
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, 2018 $ 1,203,404 $ 290,976 $ 51,381 $ 1,545,761 Foreign exchange translation adjustment (1,041 ) — (642 ) (1,683 ) Goodwill at September 30, 2019 $ 1,202,363 $ 290,976 $ 50,739 $ 1,544,078 The Company completed its annual goodwill impairment test as of July 1, 2019 on its four reporting units, which are the same as its four operating segments, and no impairments were noted. The Company performed a step zero, qualitative impairment test on its 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. Intangible Assets , Net Amortization expense related to intangible assets for the three months ended September 30, 2019 and 2018 was $12.4 million and $11.7 million, respectively. The amortization expense of acquired intangible assets for the three months ended September 30, 2019 and 2018 was $8.6 million and $9.0 million, respectively. The amortization expense of internally developed capitalized software for the three months ended September 30, 2019 and 2018 was $3.8 million and $2.7 million, respectively. Amortization expense related to intangible assets for the nine months ended September 30, 2019 and 2018 was $36.2 million and $42.6 million, respectively. The amortization expense of acquired intangible assets for the nine months ended September 30, 2019 and 2018 was $26.0 million and $35.2 million, respectively. The amortization expense of internally developed capitalized software for the nine months ended September 30, 2019 and 2018 was $10.2 million and $7.4 million, respectively. The gross carrying and accumulated amortization amounts related to the Company’s identifiable intangible assets were as follows: As of September 30, December 31, 2019 2018 (in thousands) Gross intangible assets: Customer relationships $ 356,700 $ 356,700 Trademarks/trade names 208,320 208,320 Technology/software 256,778 238,692 Proprietary data 28,627 28,627 Subtotal 850,425 832,339 Foreign exchange translation adjustment (11,028 ) (9,569 ) Total gross intangible assets $ 839,397 $ 822,770 Accumulated amortization: Customer relationships $ (226,215 ) $ (209,867 ) Trademarks/trade names (131,580 ) (123,345 ) Technology/software (209,262 ) (198,974 ) Proprietary data (13,517 ) (12,197 ) Subtotal (580,574 ) (544,383 ) Foreign exchange translation adjustment 3,119 2,416 Total accumulated amortization $ (577,455 ) $ (541,967 ) Net intangible assets: Customer relationships $ 130,485 $ 146,833 Trademarks/trade names 76,740 84,975 Technology/software 47,516 39,718 Proprietary data 15,110 16,430 Subtotal 269,851 287,956 Foreign exchange translation adjustment (7,909 ) (7,153 ) Total net intangible assets $ 261,942 $ 280,803 The following table presents the estimated amortization expense for the remainder of the year ending December 31, 2019 and succeeding years: Years Ending December 31, Amortization Expense (in thousands) Remainder of 2019 $ 13,548 2020 51,525 2021 47,483 2022 39,738 2023 33,694 Thereafter 75,954 Total $ 261,942

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2019
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 Notes. The Company has issued an aggregate of $2,600.0 million in senior unsecured notes (collectively, the “Senior Notes”) in the four discrete private offerings presented in the following table: Principal Amount Outstanding at Carrying Value at Carrying Value at Fair Value at Fair Value at Maturity Date September 30, 2019 September 30, 2019 December 31, 2018 September 30, 2019 December 31, 2018 (in thousands) Long-term debt 5.25% senior unsecured notes due 2024 November 15, 2024 $ 800,000 $ 793,934 $ 793,054 $ 827,104 $ 802,576 5.75% senior unsecured notes due 2025 August 15, 2025 800,000 793,801 793,016 842,432 807,088 4.75% senior unsecured notes due 2026 August 1, 2026 500,000 495,419 494,916 525,690 475,520 5.375% senior unsecured notes due 2027 May 15, 2027 500,000 495,005 494,516 536,960 489,745 Total long-term debt $ 2,600,000 $ 2,578,159 $ 2,575,502 $ 2,732,186 $ 2,574,929 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 $800.0 million aggregate principal amount of 5.25% senior unsecured notes due 2024 (the “2024 Senior Notes”) are scheduled to mature and be paid in full on November 15, 2024. At any time prior to November 15, 2019, the Company may redeem all or part of the 2024 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 2024 Senior Notes, together with accrued and unpaid interest, on or after November 15, 2019, at redemption prices set forth in the indenture governing the 2024 Senior Notes. The $800.0 million aggregate principal amount of 5.75% senior unsecured notes due 2025 (the “2025 Senior Notes”) are scheduled to mature and be paid in full on August 15, 2025. At any time prior to August 15, 2020, the Company may redeem all or part of the 2025 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 2025 Senior Notes, together with accrued and unpaid interest, on or after August 15, 2020, at redemption prices set forth in the indenture governing the 2025 Senior Notes. 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. Interest payments attributable to the 2024 Senior Notes and 2027 Senior Notes are due on May 15th and November 15th of each year. Interest payments attributable to the 2025 Senior Notes are due on February 15th and August 15th of each year. Interest payments attributable to the 2026 Senior Notes are due on February 1st and August 1st of each year. 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 term. On May 15, 2018, the Company entered into Amendment No. 2 (the “Second Amendment”) to the Revolving Credit Agreement. The Second Amendment, among other things, (i) increased aggregate commitments available to be borrowed to $250.0 million, (ii) extended the term to May 2023 with an option to extend for an additional one-year term and (iii) decreased the applicable rate and applicable fee rate for loans and commitments. At September 30, 2019, 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 and Second Amendments, the Company paid certain fees which, together with the existing fees related to prior credit facilities, are being amortized over their related lives. At September 30, 2019, $23.3 million of the deferred financing fees remain unamortized, $0.4 million of which is included in “Prepaid and other assets,” $1.1 million of which is included in “Other non-current assets” and $21.8 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, 2019
Leases [Abstract]
Leases	8. LEASES MSCI leases office space, data centers and certain equipment under non-cancellable operating lease agreements and determines if an arrangement is a lease at inception. The Company’s leases have remaining lease terms of up to approximately 13 years. Operating lease assets, net of initial direct costs and accumulated amortization are reflected in “Right of use assets,” with the corresponding present value of operating lease liabilities included in “Other accrued liabilities” and “Long-term operating lease liabilities” in the Unaudited Condensed Consolidated Statement of Financial Condition. Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized on the commencement date based on the present value of lease payments over the lease term. MSCI uses its incremental borrowing rate based on the information available on the commencement date in determining the present value of lease payments. The incremental borrowing rate reflects the rate of interest that MSCI would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. The Company determined its incremental borrowing rates by starting with the rates on its currently outstanding Senior Notes and making adjustments for collateralization and the relevant duration of the associated leases. The lease terms include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense is recognized on a straight-line basis over the lease term and is included in “Operating expenses” in the Unaudited Condensed Consolidated Statement of Income. Some of the Company’s lease agreements include rental payments adjusted periodically for inflation which are accounted for under ASC Subtopic 842-10, “Leases,” as variable lease amounts but are not reflected as a component of the Company’s lease liability. Certain leases also require the Company to pay real estate taxes, insurance, maintenance and other “Operating expenses” associated with the leased premises or equipment which are also not reflected as a component of the Company’s lease liability. While these expenses are also classified in “Operating expenses,” consistent with similar costs for office locations or equipment, they are not included as a component of the Company’s lease liability. The Company also subleases a small portion of its leased office space to third parties. Under ASC Subtopic 842-10, the Company recognized a total of $7.2 million of operating lease expenses for the three months ended September 30, 2019 and $21.7 million of operating lease expenses for the nine months ended September 30, 2019. The amounts associated with variable lease costs, short-term lease costs and sublease income were not significant for both the three and nine months ended September 30, 2019. For both the three and nine months ended September 30, 2018, the Company followed ASC Subtopic 840-10, “Leases,” which required the recognition of rent expense on a straight-line basis over the lease period. Rent expense for office space, including real estate taxes, insurance, maintenance and other operating expenses associated with the leased premises, for the three and nine months ended September 30, 2018 was $6.0 million and $18.8 million, respectively. Future minimum commitments for the Company’s operating leases accounted for in accordance with ASC Subtopic 842-10 in place as of September 30, 2019, 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 2019 $ 5,417 2020 28,449 2021 26,232 2022 22,565 2023 21,931 After 2023 115,662 Total lease payments $ 220,256 Less: Interest (35,865 ) Present value of lease liabilities $ 184,391 Other accrued liabilities $ 20,824 Long-term operating lease liabilities $ 163,567 Future minimum commitments for the Company’s office leases accounted for in accordance with ASC Subtopic 840-10 in place as of December 31, 2018 were as follows: Years Ending December 31, Amount (in 2019 $ 25,868 2020 24,619 2021 23,452 2022 21,832 2023 21,818 Thereafter 107,800 Total $ 225,389 Lease term and discount rate for the Company’s operating leases in place as of September 30, 2019 are as follows: As of September 30, Lease Term and Discount Rate 2019 Weighted-average remaining lease term (years) 9.93 Weighted-average discount rate 3.50 % Other information for the Company’s operating leases in place for the nine months ended September 30, 2019 are as follows: Nine Months Ended Other Information September 30, (in thousands) 2019 Operating cash flows from operating leases $ 22,573 Leased assets obtained in exchange for new operating lease liabilities (1) $ 205,202 (1)

Shareholders' Equity (Deficit)

Shareholders' Equity (Deficit)	9 Months Ended
	Sep. 30, 2019
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 $1.0 billion worth of shares of the Company’s common stock (together with the $523.1 million of authorization then remaining under the 2016 Repurchase Program, the “2018 Repurchase Program”). Share repurchases made pursuant to the 2018 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, 2019, there was $706.1 million of available authorization remaining under the 2018 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, 2019 $ 147.97 690 $ 102,081 September 30, 2018 $ 149.82 1,794 $ 268,850 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 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 ) 2018 Three Months Ended March 31, $ 0.38 $ 34,848 $ 34,900 $ (52 ) Three Months Ended June 30, 0.38 34,254 33,935 319 Three Months Ended September 30, 0.58 52,263 51,763 500 Total $ 1.34 $ 121,365 $ 120,598 $ 767 Common Stock. The following table presents activity related to shares of common stock issued and repurchased during the nine months ended September 30, 2019: Common Stock Treasury Common Stock Issued Stock Outstanding Balance at December 31, 2018 130,029,926 (45,855,788 ) 84,174,138 Dividend payable/paid 502 (158 ) 344 Common stock issued and exercise of stock options 2,234,596 — 2,234,596 Shares withheld for tax withholding and exercises — (1,044,186 ) (1,044,186 ) Shares repurchased under stock repurchase programs — (689,891 ) (689,891 ) Shares issued to directors — — — Balance at March 31, 2019 132,265,024 (47,590,023 ) 84,675,001 Dividend payable/paid 136 (136 ) — Common stock issued and exercise of stock options 25,521 — 25,521 Shares withheld for tax withholding and exercises — (6,773 ) (6,773 ) Shares repurchased under stock repurchase programs — — — Shares issued to directors 1,277 (403 ) 874 Balance at June 30, 2019 132,291,958 (47,597,335 ) 84,694,623 Dividend payable/paid 154 (154 ) — Common stock issued and exercise of stock options 17,101 — 17,101 Shares withheld for tax withholding and exercises — (4,479 ) (4,479 ) Shares repurchased under stock repurchase programs — — — Shares issued to directors — — — Balance at September 30, 2019 132,309,213 (47,601,968 ) 84,707,245

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	10. INCOME TAXES The Company’s provision for income taxes was $15.9 million and $86.9 million for the nine months ended September 30, 2019 and 2018, respectively. These amounts reflect effective tax rates of 3.5% and 19.6% for the nine months ended September 30, 2019 and 2018, respectively. 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 which was impacted by certain favorable discrete items totaling $82.7 million. These discrete items primarily relate to $66.6 million of excess tax benefits recognized upon vesting 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 MSUs”) and $10.8 million of excess tax benefits on other share-based compensation recognized during the period. In addition, the effective tax rate was also impacted by a beneficial geographic mix of earnings. The effective tax rate of 19.6% for the nine months ended September 30, 2018 reflected the Company’s estimate of the effective tax rate for the period and was impacted by certain favorable discrete items totaling $19.0 million. These discrete items primarily relate to $8.8 million of excess tax benefits on share-based compensation recognized during the period and $11.8 million relate to the release of a valuation allowance previously recorded on capital loss carryforwards. The Company recognized $7.8 million of the release of the valuation allowance in the three months ended September 30, 2018 due to the execution of the agreement to sell Investor Force Holdings, Inc. (“InvestorForce”) in July 2018 and $4.0 million of the release of the valuation allowance in April 2018 related to the Financial Engineering Associates, Inc. (“FEA”) divestiture, which was used to offset the capital gain realized on the FEA divestiture. The discrete items also include a $1.6 million net adjustment benefit relating to the adjustment resulting from the Company’s provisional accounting for the effects of the Tax Cuts and Jobs Act that was enacted on December 22, 2017 (“Tax Reform”). The Company is under examination by the IRS and other tax authorities in certain jurisdictions, including foreign jurisdictions, such as 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 2006 through 2018. As a result of having previously been a member of the Morgan Stanley consolidated group, the Company may have future settlements with Morgan Stanley related to the ultimate disposition of their New York State and New York City examination relating to the tax years 2007 and 2008 and their IRS examination relating to the tax years 2006 through 2008. The Company does not believe it has any material exposure to the New York State and New York City income tax examinations. Additionally, the Company believes it has adequate reserves for any tax issues that may arise out of the IRS examination relating to the tax years 2006 through 2008 and therefore does not believe any related settlement with Morgan Stanley will have a material impact. 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 $6.0 million in the next twelve months as a result of the resolution of tax examinations.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Segment Information	11. SEGMENT INFORMATION ASC Subtopic 280-10, “Segment Reporting,” 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 MSUs, 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 revenue, 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 four operating segments: Index, Analytics, ESG and Real Estate. The Index operating segment is primarily a provider of equity indexes. The indexes are used in many areas of the investment process, including index-linked product creation and performance benchmarking, as well as portfolio construction and rebalancing 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, or through third party applications or directly on their own platforms. The Analytics operating segment also provides various managed services to help clients operate more efficiently as well as to address the needs of certain specialized areas of the investment community by providing a reporting service and performance reporting tools to institutional consultants and investors in hedge funds. The ESG operating segment offers products and services that help institutional investors understand how ESG factors can impact the long-term risk of their 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 includes 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 operating segments of ESG and Real Estate do not individually meet the segment reporting thresholds and have been combined and presented as part of All Other for disclosure purposes. The following table presents operating revenue by reportable segment for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2019 2018 2019 2018 (in thousands) Operating revenues Index $ 237,427 $ 210,194 $ 677,750 $ 625,042 Analytics 123,603 119,898 368,719 358,004 All Other 33,221 27,842 104,721 89,250 Total $ 394,251 $ 357,934 $ 1,151,190 $ 1,072,296 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, 2019 2018 2019 2018 (in thousands) Index Adjusted EBITDA $ 177,680 $ 154,477 $ 493,806 $ 457,923 Analytics Adjusted EBITDA 37,797 37,046 113,266 106,966 All Other Adjusted EBITDA 5,312 4,014 23,220 17,782 Total operating segment profitability 220,789 195,537 630,292 582,671 2016 multi-year MSUs grant payroll tax expense — — 15,389 — Amortization of intangible assets 12,361 11,681 36,167 42,556 Depreciation and amortization of property, equipment and leasehold improvements 7,209 7,453 22,464 23,035 Operating income 201,219 176,403 556,272 517,080 Other expense (income), net 32,471 29,557 99,487 74,473 Provision for income taxes 31,765 23,014 15,920 86,854 Net income $ 136,983 $ 123,832 $ 440,865 $ 355,753 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, 2019 2018 2019 2018 (in thousands) Operating revenues Americas: United States $ 177,154 $ 167,415 $ 516,568 $ 498,270 Other 15,878 15,118 48,669 43,529 Total Americas 193,032 182,533 565,237 541,799 Europe, the Middle East and Africa ("EMEA"): United Kingdom 60,856 52,997 174,984 159,699 Other 80,022 69,602 237,745 218,999 Total EMEA 140,878 122,599 412,729 378,698 Asia & Australia: Japan 18,171 16,572 52,838 48,941 Other 42,170 36,230 120,386 102,858 Total Asia & Australia 60,341 52,802 173,224 151,799 Total $ 394,251 $ 357,934 $ 1,151,190 $ 1,072,296 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, 2019 2018 (in thousands) Long-lived assets Americas: United States $ 1,784,628 $ 1,803,321 Other 6,397 6,560 Total Americas 1,791,025 1,809,881 EMEA: United Kingdom 76,431 80,039 Other 16,948 19,369 Total EMEA 93,379 99,408 Asia & Australia: Japan 378 411 Other 7,653 7,741 Total Asia & Australia 8,031 8,152 Total $ 1,892,435 $ 1,917,441

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2019
Subsequent Events [Abstract]
Subsequent Events	12. SUBSEQUENT EVENTS On October 2, 2019, MSCI completed the acquisition of Carbon Delta AG (“Carbon Delta”), an environmental fintech and data analytics firm specializing in climate change scenario analysis for approximately $18.0 million in cash. Carbon Delta will be part of ESG within the All Other segment. The impact of this acquisition is not material to the All Other segment or the Company as a whole. On October 29, 2019, the Board of Directors authorized a stock repurchase program for the purchase of up to $750.0 million worth of shares of the Company’s common stock which will be aggregated with the $706.1 million of authorization remaining under the 2018 Repurchase Program as of September 30, 2019. On October 29, 2019, the Board of Directors declared a quarterly cash dividend of $0.68 per share for the three months ending December 31, 2019 (“fourth quarter 2019”). The fourth quarter 2019 dividend is payable on November 27, 2019 to shareholders of record as of the close of trading on November 15, 2019.

Introduction and Basis of Pre_2

Introduction and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2019
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 subsidiaries and include all adjustments of a normal, recurring nature necessary to state fairly the financial condition as of September 30, 2019 and December 31, 2018, the results of operations, comprehensive income and shareholders’ equity (deficit) for the three and nine months ended September 30, 2019 and 2018 and cash flows for the nine months ended September 30, 2019 and 2018. The unaudited condensed consolidated statement of financial condition and related financial statement information as of December 31, 2018 have been derived from the 2018 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, 2018. 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, 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, 2019 and 2018, BlackRock, Inc. accounted for 11.5% and 12.2% of the Company’s consolidated operating revenues, respectively. For the nine months ended September 30, 2019 and 2018, BlackRock, Inc. accounted for 18.9% and 20.7% 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, 2019 and 2018.
Recent Accounting Standards Updates	In February 2016, the FASB issued Accounting Standards Update No. 2016-02, “ Leases (Topic 842) In July 2018, the FASB issued Accounting Standards Update No. 2018-10, “Codification Improvements to Topic 842, Leases,” “Targeted Improvements,” The Company adopted ASU 2016-02 effective January 1, 2019 using the optional transition method available under ASU 2018-11. In preparation for adoption of the guidance, the Company implemented internal controls and processes to enable the preparation of financial information. MSCI elected to apply the transition package of practical expedients permitted within the new guidance which, among other things, allowed the Company to carry forward the historical lease classification. In addition, MSCI elected the hindsight practical expedient to determine the reasonably certain lease term for existing leases. The Company made an election to apply the exemption allowed under ASU 2016-02 for leases with an initial term of 12 months or less to not be recorded in the Condensed Consolidated Statement of Financial Condition and to only recognize the related amounts in the Condensed Consolidated Statement of Income on a straight-line basis over the lease term. See Note 8, “Leases” of the Notes to the Unaudited Condensed Consolidated Financial Statements included herein for further information regarding leases. In August 2018, the FASB issued Accounting Standards Update No. 2018-15, “ Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract,

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2019
Revenue From Contract With Customer [Abstract]
Disaggregation of Revenue	The tables that follow present the disaggregated revenues for the periods indicated (in thousands): For the Three Months ended September 30, 2019 Segments 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 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 For the Three Months ended September 30, 2018 Segments Index Analytics All Other Total Revenue Types Recurring subscriptions $ 121,285 $ 118,857 $ 27,234 $ 267,376 Asset-based fees 82,007 — — 82,007 Non-recurring 6,902 1,041 608 8,551 Total $ 210,194 $ 119,898 $ 27,842 $ 357,934 For the Nine Months ended September 30, 2018 Segments Index Analytics All Other Total Revenue Types Recurring subscriptions $ 354,116 $ 354,629 $ 86,185 $ 794,930 Asset-based fees 255,126 — — 255,126 Non-recurring 15,800 3,375 3,065 22,240 Total $ 625,042 $ 358,004 $ 89,250 $ 1,072,296
Schedule of Change in Accounts Receivable and Deferred Revenue	The table that follows presents the change in accounts receivable and in deferred revenue between the dates indicated (in thousands): Accounts receivable Deferred revenue 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, 2019 (in thousands) First 12-month period $ 301,420 Second 12-month period 167,628 Third 12-month period 61,866 Periods thereafter 24,577 Total $ 555,491

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2019
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, 2019 2018 2019 2018 (in thousands, except per share data) Net income $ 136,983 $ 123,832 $ 440,865 $ 355,753 Basic weighted average common shares outstanding 84,765 88,796 84,591 89,323 Effect of dilutive securities: Stock options and restricted stock units 785 2,576 942 2,520 Diluted weighted average common shares outstanding 85,550 91,372 85,533 91,843 Earnings per basic common share $ 1.62 $ 1.39 $ 5.21 $ 3.98 Earnings per diluted common share $ 1.60 $ 1.36 $ 5.15 $ 3.87

Property, Equipment and Lease_2

Property, Equipment and Leasehold Improvements, Net (Tables)	9 Months Ended
	Sep. 30, 2019
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, 2019 2018 (in thousands) Computer & related equipment $ 172,811 $ 200,414 Furniture & fixtures 12,157 12,033 Leasehold improvements 51,695 53,429 Work-in-process 9,823 10,506 Subtotal 246,486 276,382 Accumulated depreciation and amortization (160,071 ) (185,505 ) Property, equipment and leasehold improvements, net $ 86,415 $ 90,877

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets, Net (Tables)	9 Months Ended
	Sep. 30, 2019
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, 2018 $ 1,203,404 $ 290,976 $ 51,381 $ 1,545,761 Foreign exchange translation adjustment (1,041 ) — (642 ) (1,683 ) Goodwill at September 30, 2019 $ 1,202,363 $ 290,976 $ 50,739 $ 1,544,078
Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Identifiable Intangible Assets	The gross carrying and accumulated amortization amounts related to the Company’s identifiable intangible assets were as follows: As of September 30, December 31, 2019 2018 (in thousands) Gross intangible assets: Customer relationships $ 356,700 $ 356,700 Trademarks/trade names 208,320 208,320 Technology/software 256,778 238,692 Proprietary data 28,627 28,627 Subtotal 850,425 832,339 Foreign exchange translation adjustment (11,028 ) (9,569 ) Total gross intangible assets $ 839,397 $ 822,770 Accumulated amortization: Customer relationships $ (226,215 ) $ (209,867 ) Trademarks/trade names (131,580 ) (123,345 ) Technology/software (209,262 ) (198,974 ) Proprietary data (13,517 ) (12,197 ) Subtotal (580,574 ) (544,383 ) Foreign exchange translation adjustment 3,119 2,416 Total accumulated amortization $ (577,455 ) $ (541,967 ) Net intangible assets: Customer relationships $ 130,485 $ 146,833 Trademarks/trade names 76,740 84,975 Technology/software 47,516 39,718 Proprietary data 15,110 16,430 Subtotal 269,851 287,956 Foreign exchange translation adjustment (7,909 ) (7,153 ) Total net intangible assets $ 261,942 $ 280,803
Estimated Amortization Expense for Remainder of 2019 and Succeeding Years	The following table presents the estimated amortization expense for the remainder of the year ending December 31, 2019 and succeeding years: Years Ending December 31, Amortization Expense (in thousands) Remainder of 2019 $ 13,548 2020 51,525 2021 47,483 2022 39,738 2023 33,694 Thereafter 75,954 Total $ 261,942

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2019
Commitments And Contingencies Disclosure [Abstract]
Schedule of Senior Unsecured Notes	The Company has issued an aggregate of $2,600.0 million in senior unsecured notes (collectively, the “Senior Notes”) in the four discrete private offerings presented in the following table: Principal Amount Outstanding at Carrying Value at Carrying Value at Fair Value at Fair Value at Maturity Date September 30, 2019 September 30, 2019 December 31, 2018 September 30, 2019 December 31, 2018 (in thousands) Long-term debt 5.25% senior unsecured notes due 2024 November 15, 2024 $ 800,000 $ 793,934 $ 793,054 $ 827,104 $ 802,576 5.75% senior unsecured notes due 2025 August 15, 2025 800,000 793,801 793,016 842,432 807,088 4.75% senior unsecured notes due 2026 August 1, 2026 500,000 495,419 494,916 525,690 475,520 5.375% senior unsecured notes due 2027 May 15, 2027 500,000 495,005 494,516 536,960 489,745 Total long-term debt $ 2,600,000 $ 2,578,159 $ 2,575,502 $ 2,732,186 $ 2,574,929

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Summary of Future Maturity of Lease Liabilities Under Operating Leases	Future minimum commitments for the Company’s operating leases accounted for in accordance with ASC Subtopic 842-10 in place as of September 30, 2019, 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 2019 $ 5,417 2020 28,449 2021 26,232 2022 22,565 2023 21,931 After 2023 115,662 Total lease payments $ 220,256 Less: Interest (35,865 ) Present value of lease liabilities $ 184,391 Other accrued liabilities $ 20,824 Long-term operating lease liabilities $ 163,567 Future minimum commitments for the Company’s office leases accounted for in accordance with ASC Subtopic 840-10 in place as of December 31, 2018 were as follows: Years Ending December 31, Amount (in 2019 $ 25,868 2020 24,619 2021 23,452 2022 21,832 2023 21,818 Thereafter 107,800 Total $ 225,389
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, 2019 are as follows: As of September 30, Lease Term and Discount Rate 2019 Weighted-average remaining lease term (years) 9.93 Weighted-average discount rate 3.50 %
Summary of Other Information Under Operating Leases	Other information for the Company’s operating leases in place for the nine months ended September 30, 2019 are as follows: Nine Months Ended Other Information September 30, (in thousands) 2019 Operating cash flows from operating leases $ 22,573 Leased assets obtained in exchange for new operating lease liabilities (1) $ 205,202 (1)

Shareholders' Equity (Deficit)

Shareholders' Equity (Deficit) (Tables)	9 Months Ended
	Sep. 30, 2019
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, 2019 $ 147.97 690 $ 102,081 September 30, 2018 $ 149.82 1,794 $ 268,850
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 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 ) 2018 Three Months Ended March 31, $ 0.38 $ 34,848 $ 34,900 $ (52 ) Three Months Ended June 30, 0.38 34,254 33,935 319 Three Months Ended September 30, 0.58 52,263 51,763 500 Total $ 1.34 $ 121,365 $ 120,598 $ 767
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, 2019: Common Stock Treasury Common Stock Issued Stock Outstanding Balance at December 31, 2018 130,029,926 (45,855,788 ) 84,174,138 Dividend payable/paid 502 (158 ) 344 Common stock issued and exercise of stock options 2,234,596 — 2,234,596 Shares withheld for tax withholding and exercises — (1,044,186 ) (1,044,186 ) Shares repurchased under stock repurchase programs — (689,891 ) (689,891 ) Shares issued to directors — — — Balance at March 31, 2019 132,265,024 (47,590,023 ) 84,675,001 Dividend payable/paid 136 (136 ) — Common stock issued and exercise of stock options 25,521 — 25,521 Shares withheld for tax withholding and exercises — (6,773 ) (6,773 ) Shares repurchased under stock repurchase programs — — — Shares issued to directors 1,277 (403 ) 874 Balance at June 30, 2019 132,291,958 (47,597,335 ) 84,694,623 Dividend payable/paid 154 (154 ) — Common stock issued and exercise of stock options 17,101 — 17,101 Shares withheld for tax withholding and exercises — (4,479 ) (4,479 ) Shares repurchased under stock repurchase programs — — — Shares issued to directors — — — Balance at September 30, 2019 132,309,213 (47,601,968 ) 84,707,245

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2019
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, 2019 2018 2019 2018 (in thousands) Operating revenues Index $ 237,427 $ 210,194 $ 677,750 $ 625,042 Analytics 123,603 119,898 368,719 358,004 All Other 33,221 27,842 104,721 89,250 Total $ 394,251 $ 357,934 $ 1,151,190 $ 1,072,296
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, 2019 2018 2019 2018 (in thousands) Index Adjusted EBITDA $ 177,680 $ 154,477 $ 493,806 $ 457,923 Analytics Adjusted EBITDA 37,797 37,046 113,266 106,966 All Other Adjusted EBITDA 5,312 4,014 23,220 17,782 Total operating segment profitability 220,789 195,537 630,292 582,671 2016 multi-year MSUs grant payroll tax expense — — 15,389 — Amortization of intangible assets 12,361 11,681 36,167 42,556 Depreciation and amortization of property, equipment and leasehold improvements 7,209 7,453 22,464 23,035 Operating income 201,219 176,403 556,272 517,080 Other expense (income), net 32,471 29,557 99,487 74,473 Provision for income taxes 31,765 23,014 15,920 86,854 Net income $ 136,983 $ 123,832 $ 440,865 $ 355,753
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, 2019 2018 2019 2018 (in thousands) Operating revenues Americas: United States $ 177,154 $ 167,415 $ 516,568 $ 498,270 Other 15,878 15,118 48,669 43,529 Total Americas 193,032 182,533 565,237 541,799 Europe, the Middle East and Africa ("EMEA"): United Kingdom 60,856 52,997 174,984 159,699 Other 80,022 69,602 237,745 218,999 Total EMEA 140,878 122,599 412,729 378,698 Asia & Australia: Japan 18,171 16,572 52,838 48,941 Other 42,170 36,230 120,386 102,858 Total Asia & Australia 60,341 52,802 173,224 151,799 Total $ 394,251 $ 357,934 $ 1,151,190 $ 1,072,296
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, 2019 2018 (in thousands) Long-lived assets Americas: United States $ 1,784,628 $ 1,803,321 Other 6,397 6,560 Total Americas 1,791,025 1,809,881 EMEA: United Kingdom 76,431 80,039 Other 16,948 19,369 Total EMEA 93,379 99,408 Asia & Australia: Japan 378 411 Other 7,653 7,741 Total Asia & Australia 8,031 8,152 Total $ 1,892,435 $ 1,917,441

Introduction and Basis of Pre_3

Introduction and Basis of Presentation - Additional Information (Detail) - Sales Revenue, Services, Net [Member] - Customer Concentration Risk [Member] - Customer	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Blackrock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	11.50%	12.20%
Index [Member] | Blackrock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	18.90%	20.70%
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

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 394,251	$ 357,934	$ 1,151,190	$ 1,072,296
Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	237,427	210,194	677,750	625,042
Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	123,603	119,898	368,719	358,004
All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	33,221	27,842	104,721	89,250
Recurring Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	288,108	267,376	859,621	794,930
Recurring Subscriptions [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	133,403	121,285	393,222	354,116
Recurring Subscriptions [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	122,120	118,857	363,929	354,629
Recurring Subscriptions [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	32,585	27,234	102,470	86,185
Asset-based Fees [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	96,013	82,007	265,554	255,126
Asset-based Fees [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	96,013	82,007	265,554	255,126
Non-recurring [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	10,130	8,551	26,015	22,240
Non-recurring [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	8,011	6,902	18,974	15,800
Non-recurring [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	1,483	1,041	4,790	3,375
Non-recurring [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 636	$ 608	$ 2,251	$ 3,065

Revenue Recognition - Schedule

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

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Revenue From Contract With Customer [Abstract]
Revenue recognized during period included in deferred revenue	$ 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, 2019USD ($)
Revenue Recognition [Line Items]
Remaining performance obligations	$ 555,491
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	301,420
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	167,628
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	61,866
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 24,577

Revenue Recognition - Schedul_3

Revenue Recognition - Schedule of Remaining Performance Obligations (Detail 1) $ in Thousands	Sep. 30, 2019USD ($)
Revenue From Contract With Customer [Abstract]
Remaining performance obligations	$ 555,491

Revenue Recognition - Schedul_4

Revenue Recognition - Schedule of Remaining Performance Obligations (Parenthetical) (Detail)	Sep. 30, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-10-01
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: 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

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, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net income	$ 136,983	$ 125,690	$ 178,192	$ 123,832	$ 116,829	$ 115,092	$ 440,865	$ 355,753
Basic weighted average common shares outstanding	84,765			88,796			84,591	89,323
Effect of dilutive securities:
Stock options and restricted stock units	785			2,576			942	2,520
Diluted weighted average common shares outstanding	85,550			91,372			85,533	91,843
Earnings per basic common share	$ 1.62			$ 1.39			$ 5.21	$ 3.98
Earnings per diluted common share	$ 1.60			$ 1.36			$ 5.15	$ 3.87

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, 2019	Dec. 31, 2018
Property Plant And Equipment [Abstract]
Computer & related equipment	$ 172,811	$ 200,414
Furniture & fixtures	12,157	12,033
Leasehold improvements	51,695	53,429
Work-in-process	9,823	10,506
Subtotal	246,486	276,382
Accumulated depreciation and amortization	(160,071)	(185,505)
Property, equipment and leasehold improvements, net	$ 86,415	$ 90,877

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, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Property Plant And Equipment [Abstract]
Depreciation and amortization of property, equipment and leasehold improvements	$ 7,209	$ 7,453	$ 22,464	$ 23,035

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets, Net - Schedule of Goodwill by Reportable Segment (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2019USD ($)
Goodwill [Line Items]
Goodwill, Beginning balance	$ 1,545,761
Foreign exchange translation adjustment	(1,683)
Goodwill, Ending balance	1,544,078
Index [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	1,203,404
Foreign exchange translation adjustment	(1,041)
Goodwill, Ending balance	1,202,363
Analytics [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	290,976
Goodwill, Ending balance	290,976
All Other [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	51,381
Foreign exchange translation adjustment	(642)
Goodwill, Ending balance	$ 50,739

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets, Net - Additional Information (Detail)	Jul. 01, 2019USD ($)Segment	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)Segment	Sep. 30, 2018USD ($)
Goodwill [Line Items]
Number of reporting units | Segment	4
Number of operating segments | Segment	4			4
Impairment of goodwill	$ 0
Amortization of intangible assets		$ 12,361,000	$ 11,681,000	$ 36,167,000	$ 42,556,000
Acquired Intangible Assets [Member]
Goodwill [Line Items]
Amortization of intangible assets		8,600,000	9,000,000	26,000,000	35,200,000
Capitalized Software [Member]
Goodwill [Line Items]
Amortization of intangible assets		$ 3,800,000	$ 2,700,000	$ 10,200,000	$ 7,400,000

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets, Net - Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Identifiable Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	$ 850,425	$ 832,339
Foreign exchange translation adjustment	(11,028)	(9,569)
Gross carrying value	839,397	822,770
Accumulated amortization excluding foreign exchange translation adjustment	(580,574)	(544,383)
Foreign exchange translation adjustment	3,119	2,416
Accumulated amortization	(577,455)	(541,967)
Net carrying value excluding foreign exchange translation adjustment	269,851	287,956
Foreign exchange translation adjustment	(7,909)	(7,153)
Net carrying value	261,942	280,803
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	(226,215)	(209,867)
Net carrying value excluding foreign exchange translation adjustment	130,485	146,833
Trademarks/Trade Names [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	208,320	208,320
Accumulated amortization excluding foreign exchange translation adjustment	(131,580)	(123,345)
Net carrying value excluding foreign exchange translation adjustment	76,740	84,975
Technology/Software [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value excluding foreign exchange translation adjustment	256,778	238,692
Accumulated amortization excluding foreign exchange translation adjustment	(209,262)	(198,974)
Net carrying value excluding foreign exchange translation adjustment	47,516	39,718
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	(13,517)	(12,197)
Net carrying value excluding foreign exchange translation adjustment	$ 15,110	$ 16,430

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets, Net - Estimated Amortization Expense for Remainder of 2019 and Succeeding Years (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Remainder of 2019	$ 13,548
2020	51,525
2021	47,483
2022	39,738
2023	33,694
Thereafter	75,954
Net carrying value	$ 261,942	$ 280,803

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	May 15, 2018	Aug. 04, 2016	Sep. 30, 2019	Nov. 20, 2014
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount			$ 2,600,000,000
Prepaid and Other Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			400,000
Other Non-Current Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			1,100,000
Long-term Debt [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			$ 21,800,000
Revolving Credit Agreement [Member]
Schedule Of Commitments And Contingencies [Line Items]
Revolving credit facility, maximum borrowing	$ 250,000,000	$ 220,000,000		$ 200,000,000
Revolving credit agreement, term			5 years
Revolving credit agreement, extended term	1 year	1 year
5.250% Senior Unsecured Notes Due 2024 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount			$ 800,000,000
Debt instrument interest rate			5.25%
Maturity date			Nov. 15, 2024
Redemption description			At any time prior to November 15, 2019, the Company may redeem all or part of the 2024 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.
5.75% 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%
Maturity date			Aug. 15, 2025
Redemption description			At any time prior to August 15, 2020, the Company may redeem all or part of the 2025 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.
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%
Senior Notes [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount			$ 2,600,000,000
Senior Notes and Revolving Credit Facility [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			$ 23,300,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Senior Unsecured Notes (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Principal Amount Outstanding	$ 2,600,000,000
Carrying Value	2,578,159,000	$ 2,575,502,000
Fair Value	$ 2,732,186,000	2,574,929,000
5.25% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Maturity Date	Nov. 15, 2024
Principal Amount Outstanding	$ 800,000,000
Carrying Value	793,934,000	793,054,000
Fair Value	$ 827,104,000	802,576,000
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	793,801,000	793,016,000
Fair Value	$ 842,432,000	807,088,000
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	495,419,000	494,916,000
Fair Value	$ 525,690,000	475,520,000
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	495,005,000	494,516,000
Fair Value	$ 536,960,000	$ 489,745,000

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Senior Unsecured Notes (Parenthetical) (Detail)	Sep. 30, 2019
5.25% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.25%
5.75% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	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%

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Lessee Lease Description [Line Items]
Operating lease, existence of option to extend			true
Operating lease, options to extend			Some of these leases have options to extend which, if exercised, would extend the maximum term to approximately 23 years.
Operating lease, existence of option to terminate			true
Operating lease, options to terminate			Some of the leases also provide for early termination, the exercise of which would shorten the term of those leases by up to 5 years.
Operating lease, expense	$ 7.2		$ 21.7
Rent expense for office space		$ 6		$ 18.8
Maximum [Member]
Lessee Lease Description [Line Items]
Operating lease, remaining lease terms			13 years
Operating lease, extended term	23 years		23 years
Operating lease, early termination term			5 years

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Commitments Under Operating Leases with ASC 842 (Detail) $ in Thousands	Sep. 30, 2019USD ($)
Maturity of Lease Liabilities
Remainder of 2019	$ 5,417
2020	28,449
2021	26,232
2022	22,565
2023	21,931
After 2023	115,662
Total lease payments	220,256
Less: Interest	(35,865)
Present value of lease liabilities	184,391
Other accrued liabilities	$ 20,824
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherAccruedLiabilitiesCurrent
Long-term operating lease liabilities	$ 163,567

Leases - Summary of Future Mi_2

Leases - Summary of Future Minimum Commitments Under Operating Leases with ASC 840 (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 25,868
2020	24,619
2021	23,452
2022	21,832
2023	21,818
Thereafter	107,800
Total	$ 225,389

Leases - Summary of Lease Term

Leases - Summary of Lease Term and Discount Rate Under Operating Lease (Detail)	Sep. 30, 2019
Leases [Abstract]
Weighted-average remaining lease term (years)	9 years 11 months 4 days
Weighted-average discount rate	3.50%

Leases - Summary of Other Infor

Leases - Summary of Other Information Under Operating Lease (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2019USD ($)
Leases [Abstract]
Operating cash flows from operating leases	$ 22,573
Leased assets obtained in exchange for new operating lease liabilities(1)	$ 205,202

Leases - Summary of Other Inf_2

Leases - Summary of Other Information Under Operating Lease (Parenthetical) (Detail) - USD ($) $ in Thousands	Jan. 01, 2019	Sep. 30, 2019
Lessee Lease Description [Line Items]
Leased assets obtained in exchange for new operating lease liabilities(1)		$ 205,202
Restatement Adjustment [Member] | ASU 2016-02 [Member]
Lessee Lease Description [Line Items]
Leased assets obtained in exchange for new operating lease liabilities(1)	$ 197,500

Shareholders' Equity (Deficit_2

Shareholders' Equity (Deficit) - Additional Information (Detail) - USD ($)	Sep. 30, 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]
Stock repurchase program, remaining authorized repurchase amount	$ 706,100,000
Repurchase program authorizing the additional purchase of shares		$ 1,000,000,000

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
	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Equity, Class of Treasury Stock [Line Items]
Dollar Value of Shares Repurchased	$ 102,081	$ 45,606	$ 154,898	$ 68,345
Open Market Purchases of Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Average Price Paid Per Share					$ 147.97	$ 149.82
Total Number of Shares Repurchased					690	1,794
Dollar Value of Shares Repurchased					$ 102,081	$ 268,850

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, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Stockholders Equity [Abstract]
Dividend declared per common share	$ 0.68	$ 0.58	$ 0.58	$ 0.58	$ 0.38	$ 0.38	$ 1.84	$ 1.34
Cash dividends declared, Amount	$ 58,176	$ 49,613	$ 55,339	$ 52,263	$ 34,254	$ 34,848	$ 163,128	$ 121,365
Cash dividends distributed, Amount	57,882	49,365	57,988	51,763	33,935	34,900	165,235	120,598
Cash dividends (released)/deferred, Amount	$ 294	$ 248	$ (2,649)	$ 500	$ 319	$ (52)	$ (2,107)	$ 767

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
	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2019
Common Stock Issued [Member]
Common Stock Outstanding [Line Items]
Beginning balance	132,265,024	130,029,926	130,029,926
Dividend payable/paid	136	502	154
Common stock issued and exercise of stock options	25,521	2,234,596	17,101
Shares issued to directors	1,277
Ending balance	132,291,958	132,265,024	132,309,213
Treasury Stock [Member]
Common Stock Outstanding [Line Items]
Beginning balance	(47,590,023)	(45,855,788)	(45,855,788)
Dividend payable/paid	(136)	(158)	(154)
Shares withheld for tax withholding and exercises	(6,773)	(1,044,186)	(4,479)
Shares repurchased under stock repurchase programs		(689,891)
Shares issued to directors	(403)
Ending balance	(47,597,335)	(47,590,023)	(47,601,968)
Common Stock Outstanding [Member]
Common Stock Outstanding [Line Items]
Beginning balance	84,675,001	84,174,138	84,174,138
Dividend payable/paid		344
Common stock issued and exercise of stock options	25,521	2,234,596	17,101
Shares withheld for tax withholding and exercises	(6,773)	(1,044,186)	(4,479)
Shares repurchased under stock repurchase programs		(689,891)
Shares issued to directors	874
Ending balance	84,694,623	84,675,001	84,707,245

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Examination [Line Items]
Provision for income taxes		$ 31,765	$ 23,014	$ 15,920	$ 86,854
Effective tax rate				3.50%	19.60%
Amounts effect on effective tax rate		82,700	19,000	$ 82,700	$ 19,000
Net adjustment benefit					1,600
Capital loss carry forward valuation allowance		$ 11,800		11,800
Decrease in unrecognized tax benefit				$ 6,000
Minimum [Member]
Income Tax Examination [Line Items]
Tax years under examination				2006
Maximum [Member]
Income Tax Examination [Line Items]
Tax years under examination				2018
State and Local Jurisdiction [Member] | New York State Division of Taxation and Finance [Member] | Minimum [Member] | Morgan Stanley [Member]
Income Tax Examination [Line Items]
Tax years under examination				2007
State and Local Jurisdiction [Member] | New York State Division of Taxation and Finance [Member] | Maximum [Member] | Morgan Stanley [Member]
Income Tax Examination [Line Items]
Tax years under examination				2008
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Minimum [Member] | Morgan Stanley [Member]
Income Tax Examination [Line Items]
Tax years under examination				2006
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Maximum [Member] | Morgan Stanley [Member]
Income Tax Examination [Line Items]
Tax years under examination				2008
Investor Force [Member]
Income Tax Examination [Line Items]
Valuation Allowance Recognized			$ 7,800
Financial Engineering Associates, Inc [Member]
Income Tax Examination [Line Items]
Valuation Allowance Recognized	$ 4,000
2016 Multi-year MSUs
Income Tax Examination [Line Items]
Excess tax benefit recognized upon vesting of restricted stock unit				$ 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 recognition				$ 10,800	$ 8,800

Segment Information - Additiona

Segment Information - Additional Information (Detail) - Segment	Jul. 01, 2019	Sep. 30, 2019
Segment Reporting [Abstract]
Number of operating segments	4	4

Segment Information - Operating

Segment Information - Operating Revenue by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 394,251	$ 357,934	$ 1,151,190	$ 1,072,296
Index [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	237,427	210,194	677,750	625,042
Analytics [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	123,603	119,898	368,719	358,004
All Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 33,221	$ 27,842	$ 104,721	$ 89,250

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, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 220,789			$ 195,537			$ 630,292	$ 582,671
2016 multi-year MSUs grant payroll tax expense							15,389
Amortization of intangible assets	12,361			11,681			36,167	42,556
Depreciation and amortization of property, equipment and leasehold improvements	7,209			7,453			22,464	23,035
Operating income	201,219			176,403			556,272	517,080
Other expense (income), net	32,471			29,557			99,487	74,473
Provision for income taxes	31,765			23,014			15,920	86,854
Net income	136,983	$ 125,690	$ 178,192	123,832	$ 116,829	$ 115,092	440,865	355,753
Index [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	177,680			154,477			493,806	457,923
Analytics [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	37,797			37,046			113,266	106,966
All Other [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 5,312			$ 4,014			$ 23,220	$ 17,782

Segment Information - Revenue b

Segment Information - Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 394,251	$ 357,934	$ 1,151,190	$ 1,072,296
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	177,154	167,415	516,568	498,270
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	15,878	15,118	48,669	43,529
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	193,032	182,533	565,237	541,799
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	60,856	52,997	174,984	159,699
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	80,022	69,602	237,745	218,999
Europe, the Middle East and Africa ("EMEA") [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	140,878	122,599	412,729	378,698
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	18,171	16,572	52,838	48,941
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	42,170	36,230	120,386	102,858
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 60,341	$ 52,802	$ 173,224	$ 151,799

Segment Information - Long-Live

Segment Information - Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1,892,435	$ 1,917,441
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,784,628	1,803,321
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	6,397	6,560
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,791,025	1,809,881
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	76,431	80,039
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	16,948	19,369
Total EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	93,379	99,408
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	378	411
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	7,653	7,741
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 8,031	$ 8,152

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Oct. 29, 2019	Oct. 02, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Subsequent Event [Line Items]
Quarterly dividend declared			$ 0.68	$ 0.58	$ 0.58	$ 0.58	$ 0.38	$ 0.38	$ 1.84	$ 1.34
2018 Repurchase Program [Member]
Subsequent Event [Line Items]
Stock repurchase program, remaining authorized repurchase amount			$ 706.1						$ 706.1
Subsequent Event [Member]
Subsequent Event [Line Items]
Quarterly dividend declared	$ 0.68
Quarterly dividend declared date	Oct. 29, 2019
Quarterly dividend payable date	Nov. 27, 2019
Quarterly dividend record date	Nov. 15, 2019
Subsequent Event [Member] | 2018 Repurchase Program [Member]
Subsequent Event [Line Items]
Repurchase program authorizing the purchase of shares	$ 750
Stock repurchase program, remaining authorized repurchase amount	$ 706.1
Subsequent Event [Member] | Carbon Delta [Member]
Subsequent Event [Line Items]
Business acquisition, costs		$ 18