MSCI (MSCI) 10-Q 4 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	Apr. 27, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Trading Symbol	MSCI
Entity Registrant Name	MSCI Inc.
Entity Central Index Key	1,408,198
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		89,024,288

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 849,828	$ 889,502
Accounts receivable (net of allowances of $1,861 and $1,700 at March 31, 2018 and December 31, 2017, respectively)	462,577	327,597
Prepaid income taxes	1,153	15,103
Prepaid and other assets	34,799	34,927
Total current assets	1,348,357	1,267,129
Property, equipment and leasehold improvements (net of accumulated depreciation and amortization of $177,562 and $171,280 at March 31, 2018 and December 31, 2017, respectively)	86,310	94,437
Goodwill	1,562,660	1,560,621
Intangible assets (net of accumulated amortization of $519,640 and $507,612 at March 31, 2018 and December 31, 2017, respectively)	316,259	321,836
Deferred tax assets	11,876	12,013
Other non-current assets	19,032	19,632
Total assets	3,344,494	3,275,668
Current liabilities:
Accounts payable	1,382	1,612
Income taxes payable	22,144	14,828
Accrued compensation and related benefits	45,951	131,156
Other accrued liabilities	83,106	85,710
Deferred revenue	503,298	374,365
Total current liabilities	655,881	607,671
Long-term debt	2,078,816	2,078,093
Deferred taxes	76,768	78,027
Other non-current liabilities	111,655	110,865
Total liabilities	2,923,120	2,874,656
Commitments and Contingencies (see Note 7 and Note 8)
Shareholders' equity:
Preferred stock (par value $0.01, 100,000,000 share authorized; no shares issued)
Common stock (par value $0.01; 750,000,000 common shares authorized; 129,953,761 and 129,543,856 common shares issued and 89,859,658 and 90,104,885 common shares outstanding at March 31, 2018 and December 31, 2017, respectively)	1,300	1,295
Treasury shares, at cost (40,094,103 and 39,438,971 common shares held at March 31, 2018 and December 31, 2017, respectively)	(2,413,283)	(2,321,989)
Additional paid in capital	1,276,109	1,264,849
Retained earnings	1,601,583	1,505,204
Accumulated other comprehensive loss	(44,335)	(48,347)
Total shareholders' equity	421,374	401,012
Total liabilities and shareholders' equity	$ 3,344,494	$ 3,275,668

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 1,861	$ 1,700
Property, equipment and leasehold improvements, accumulated depreciation and amortization	177,562	171,280
Intangible assets, accumulated amortization	$ 519,640	$ 507,612
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	129,953,761	129,543,856
Common stock, shares outstanding	89,859,658	90,104,885
Treasury shares	40,094,103	39,438,971

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Operating revenues	$ 351,316	$ 301,207
Operating expenses:
Cost of revenues	71,304	67,463
Selling and marketing	46,409	42,972
Research and development	20,707	18,970
General and administrative	26,187	20,981
Amortization of intangible assets	11,338	11,251
Depreciation and amortization of property, equipment and leasehold improvements	8,205	8,838
Total operating expenses	184,150	170,475
Operating income	167,166	130,732
Interest income	(2,770)	(932)
Interest expense	29,560	29,024
Other expense (income)	938	1,015
Other expense (income), net	27,728	29,107
Income before provision for income taxes	139,438	101,625
Provision for income taxes	24,346	28,674
Net income	$ 115,092	$ 72,951
Earnings per basic common share	$ 1.28	$ 0.80
Earnings per diluted common share	$ 1.24	$ 0.80
Weighted average shares outstanding used in computing earnings per share
Basic	90,075	90,708
Diluted	92,587	91,624
Dividend declared per common share	$ 0.38	$ 0.28

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 115,092	$ 72,951
Other comprehensive income (loss):
Foreign currency translation adjustments	3,962	2,941
Foreign currency translation adjustments, net	3,962	2,941
Pension and other post-retirement adjustments	(100)	(99)
Income tax effect	27	37
Pension and other post-retirement adjustments, net	(73)	(62)
Net investment hedge adjustments	123
Net investment hedge adjustments, net	123
Other comprehensive income (loss), net of tax	4,012	2,879
Comprehensive income	$ 119,104	$ 75,830

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net income	$ 115,092	$ 72,951
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	11,338	11,251
Stock-based compensation expense	9,053	9,394
Depreciation and amortization of property, equipment and leasehold improvements	8,205	8,838
Amortization of debt origination fees	849	849
Deferred taxes	(1,097)	(2,035)
Other non-cash adjustments	321	25
Changes in assets and liabilities:
Accounts receivable	(134,801)	(40,582)
Prepaid income taxes	13,626	12,438
Prepaid and other assets	192	629
Accounts payable	(230)	561
Accrued compensation and related benefits	(84,517)	(76,708)
Income taxes payable	3,001	3,755
Other accrued liabilities	(1,516)	(10,280)
Deferred revenue	148,468	43,247
Other	613	2,682
Net cash provided by operating activities	88,597	37,015
Cash flows from investing activities
Capital expenditures	(1,512)	(7,322)
Capitalized software development costs	(4,360)	(2,307)
Net cash used in investing activities	(5,872)	(9,629)
Cash flows from financing activities
Proceeds from exercise of stock options	102	625
Repurchase of treasury shares	(91,277)	(100,362)
Payment of dividends	(34,883)	(25,489)
Net cash used in financing activities	(126,058)	(125,226)
Effect of exchange rate changes	3,659	2,978
Net decrease in cash	(39,674)	(94,862)
Cash and cash equivalent, beginning of period	889,502	791,834
Cash and cash equivalent, end of period	849,828	696,972
Supplemental disclosure of cash flow information:
Cash paid for interest	35,121	34,916
Cash paid for income taxes	8,602	13,294
Supplemental disclosure of non-cash investing activities
Property, equipment and leasehold improvements accrued, but not yet paid	3,101	2,944
Supplemental disclosure of non-cash financing activities
Cash dividends declared, but not yet paid	$ 337	$ 269

Introduction and Basis of Prese

Introduction and Basis of Presentation	3 Months Ended
	Mar. 31, 2018
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 mission-critical investment decision support tools, including indexes; portfolio construction and risk management products and services; Environmental, Social and Governance (“ESG”) research and ratings; and real estate research, reporting and benchmarking offerings. MSCI’s research-derived intellectual property includes methodologies, models, derived data and algorithms, as well as applications and services, which help its clients manage their investment processes and address their investment, risk and regulatory challenges. Basis of Presentation and Use of Estimates These unaudited condensed consolidated financial statements include the accounts of MSCI Inc. and its subsidiaries and include all adjustments of a normal, recurring nature necessary to state fairly the financial condition as of March 31, 2018 and December 31, 2017, the results of operations and comprehensive income for the three months ended March 31, 2018 and 2017 and cash flows for the three months ended March 31, 2018 and 2017. The unaudited condensed consolidated statement of financial condition and related financial statement information as of December 31, 2017 have been derived from the 2017 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, 2017. 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 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. Certain prior period amounts have been reclassified to conform to the current period presentation. Concentrations For the three months ended March 31, 2018 and 2017, BlackRock, Inc. accounted for 12.9% and 10.3% of the Company’s consolidated operating revenues, respectively. For the three months ended March 31, 2018 and 2017, BlackRock, Inc. accounted for 22.1% and 18.6% of the Index segment operating revenues, respectively. No single customer represented 10.0% or more of revenues within the Analytics and All Other segments for the three months ended March 31, 2018 and 2017.

Recent Accounting Standards Upd

Recent Accounting Standards Updates	3 Months Ended
	Mar. 31, 2018
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Standards Updates	2. RECENT ACCOUNTING STANDARDS UPDATES In May 2014, the FASB issued Accounting Standards Update 2014-09, “ Revenue from Contracts with Customers (Topic 606) In March 2016, the FASB issued Accounting Standards Update 2016-08, “ Principal Versus Agent Considerations (Reporting Revenue Gross Versus Net) Identifying Performance Obligations and Licensing Narrow-Scope Improvements and Practical Expedients Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers In February 2016, the FASB issued Accounting Standards Update No. 2016-02, “ Leases (Topic 842) In June 2016, the FASB issued Accounting Standards Update No. 2016-13, “ Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In January 2017, the FASB issued Accounting Standards Update No. 2017-01, “ Business Combinations (Topic 805): Clarifying the Definition of a Business In January 2017, the FASB issued Accounting Standards Update No. 2017-04, “ Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In February 2017, the FASB issued Accounting Standards Update No. 2017-07, “ Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost In May 2017, the FASB issued Accounting Standards Update No. 2017-09, “ Compensation—Stock Compensation (Topic 718), Scope of Modification Accounting, Compensation—Stock Compensation Compensation—Stock Compensation In August 2017, the FASB issued Accounting Standards Update (“ASU”) No. 2017-12, “ Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, On December 22, 2017, the U.S. government enacted comprehensive tax legislation, the Tax Cuts and Jobs Act (“Tax Reform”). Given the significance of the legislation, the SEC staff issued Staff Accounting Bulletin No. 118, “ Income Tax Accounting Implications of the Tax Cuts and Jobs Act,

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2018
Revenue From Contract With Customer [Abstract]
Revenue Recognition	3. REVENUE RECOGNITION MSCI adopted the new revenue standard set forth under Accounting Standards Codification Topic 606 “Revenue from Contracts with Customers,” Products and Services MSCI generally licenses annual, recurring subscriptions for the majority of its Index, Analytics and ESG products and services for a fee due in advance of the service period. MSCI’s contracts are typically non-cancellable by the client and non-refundable for the term of the agreement. Fees may vary based on a number of factors including by product or service, number of users and/or volume of services. MSCI’s client contracts do not have a financing component and the consideration received is typically not variable except as noted below. MSCI also charges clients to use its indexes as the basis for index-linked investment products, such as ETFs, passively managed funds and separate accounts. These clients commonly pay MSCI a license fee, typically in arrears, primarily based on the assets under management (“AUM”) in their investment products. These fees are variable and fall within the sales-based and royalty-based exception. Certain exchanges use MSCI’s indexes as the basis for futures and options contracts and pay MSCI a license fee, typically in arrears, primarily based on the volume of trades and/or number of instruments. These fees are variable, and fall within the sales-based and royalty-based exception. Clients of MSCI’s Real Estate products subscribe to periodic benchmark reports, digests, market information and other publications. Fees are primarily paid in arrears after the product is delivered, with the exception of the market information product which is generally paid in advance. MSCI also realizes one-time fees commonly related to customized reports, historical data sets, certain derivative financial products and certain implementation and consulting services, as well as from particular products and services that are purchased on a non-renewal basis. Accounting policy The following describes MSCI’s primary types of revenues and the applicable revenue recognition policies. The Company’s revenues are primarily derived from the licensing of products and services and revenue is recognized when control of the promised goods or services is transferred to MSCI’s customers, in an amount that reflects the consideration that the Company expects to be entitled to in exchange for those goods or services. Revenue is recognized when the parties to the contract have legally enforceable obligations and are committed to performing their respective obligations, the Company can identify each party’s rights regarding the goods or services to be provided, the Company can identify the payment terms for the goods or services to be provided, the contract has commercial substance and it is probable that the Company will collect substantially all of the consideration to which it will be entitled in exchange for the goods or services that will be provided to the customer. Revenue is recognized exclusive of any applicable sales or other indirect tax withholdings. For products within MSCI’s Index segment, with respect to index data subscriptions, MSCI’s performance obligation to deliver the data is satisfied over time and, accordingly, revenue is recognized ratably over the term of the agreement. With respect to licenses to create index-linked investment products, MSCI’s performance obligation allows customers to use the Company’s intellectual property ( i.e. For products within MSCI’s Analytics segment, MSCI’s performance obligations include providing access to its proprietary models and/or hosted applications and, in some cases, delivery of managed services, which are all satisfied over time, and accordingly, revenue is recognized ratably over the term of the agreement. For implementation services, MSCI meets its performance obligation once the service is complete and is available for the client to use and revenue is recognized at the point in time in which the completion has occurred. With respect to software licenses for the Company’s energy and commodity analytics products, MSCI’s performance obligation is partially satisfied and revenue recognized at the point in time when the software’s code key is delivered to the customer, which based upon a fair value assessment, represents approximately 82.0% of the contract value. MSCI’s remaining performance obligations are the post contractual support services and revenue is recognized evenly over the course of the license term, which based on a fair value assessment, represents approximately 18.0% of the value of the software. As of April 9, 2018, MSCI divested Financial Engineering Associates, Inc. (“FEA”) and the related energy and commodity analytics product line. See Note 11, “Subsequent Events,” for further details. For products within the All Other segment, MSCI’s performance obligations under the Company’s ESG products are satisfied over time for the majority of the data subscriptions as MSCI provides and updates the data to the customer throughout the term of the agreement and revenue is recognized ratably over the term of the agreement. For custom ESG research data, the performance obligation is complete, and revenue recognized, at the point in time that the data is updated and available to the customer. With respect to the Company’s Real Estate products, MSCI primarily satisfies its performance obligations, and revenue is recognized, at the point in time when the Company delivers reports or publications or events are completed. For certain sponsorships, the performance obligation is satisfied, and revenue is recognized, over the term of the agreements. For market information products, publications are delivered throughout the year, and the revenue is recognized over time. The Company allocates the transaction price to each performance obligation based on the best estimate of the relative standalone selling price of each distinct good or service in the contract. The transaction price in the contract is allocated at contract inception to the distinct good or service underlying each performance obligation in proportion to the standalone selling prices. This standalone selling price may be the contract price, but is more often than not the best estimate of the price the Company would receive for selling the good or service to other similar customers. Discounts applied to the contract will be allocated based on the same proportion of standalone selling prices. For services where the transaction price is variable based upon AUM, volume of trades and/or number of investments linked to MSCI’s indexes, the transaction price is based upon pricing models and is not allocated at the inception of the contract but rather falls within the sales and usage based royalty exception under which the price and associated revenue are based upon actual known performance or best estimates of actual performance during the performance period. The majority of MSCI’s contracts have a duration of one year or less and, accordingly, revenue associated with these performance obligations will be recognized within 12 months. For those contracts where fees are based on AUM or trading volumes of financial products linked to the Company’s indexes, including ETFs and futures and options contracts, revenue associated with MSCI’s performance obligations is recognized over the course of the year. Determining when control has transferred can sometimes require management judgement ( e.g. MSCI has elected the Modified Retrospective Approach and as such would apply the new revenue standard only to contracts that are not completed at the adoption date and would not have adjusted prior reporting periods. The cumulative impact of adoption on the Company’s Unaudited Condensed Consolidated Statement of Financial Condition was as follows (in thousands): Selected line items As reported at December 31, 2017 Adjustments due to Adoption of ASC 606 Adjusted as of December 31, 2017 Statement of Financial Condition Accounts receivable $ 327,597 $ 145,803 $ 473,400 Income taxes payable $ 14,828 $ 4,314 $ 19,142 Other accrued liabilities $ 85,710 $ 5,128 $ 90,838 Deferred revenue $ 374,365 $ 120,226 $ 494,591 Retained earnings $ 1,505,204 $ 16,135 $ 1,521,339 Included in the above adjustments is an increase of approximately $135.5 million primarily to accounts receivable and deferred revenue with no impact to retained earnings. In accordance with the new revenue standard, the Company now records an accounts receivable and an associated contract liability, reflected as “Deferred revenue” on MSCI’s Unaudited Condensed Consolidated Statement of Financial Condition, when it bills the customer in advance of the start date of the subscription period because the Company has determined it has an unconditional right to receive cash because the contracts are non-cancellable by the client and non-refundable. Under the old revenue standard, these balances would not have been recorded as accounts receivable and deferred revenue as the contract service start date was subsequent to December 31, 2017. The impact of adopting the new revenue standard on the Company’s Unaudited Condensed Consolidated Statement of Income through the date of March 31, 2018 is as follows (in thousands): For the period ended March 31, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Income Operating revenues $ 351,316 $ (2,286 ) $ 349,030 Operating income $ 167,166 $ (2,286 ) $ 164,880 Income before provision for income taxes $ 139,438 $ (2,286 ) $ 137,152 Provision for income taxes $ 24,346 $ 457 $ 24,803 Net income $ 115,092 $ (1,829 ) $ 113,263 Earnings per basic common share $ 1.28 $ (0.02 ) $ 1.26 Earnings per diluted common share $ 1.24 $ (0.02 ) $ 1.22 The impact of adopting the new revenue standard on the Company’s Unaudited Statement of Financial Condition through the date of March 31, 2018 is as follows (in thousands): March 31, 2018 Selected line items As reported at March 31, 2018 Impact of Change Without Adoption of ASC 606 Statement of Financial Condition Accounts receivable $ 462,577 $ (91,945 ) $ 370,632 Income taxes payable $ 22,144 $ (4,771 ) $ 17,373 Other accrued liabilities $ 83,106 $ (3,456 ) $ 79,650 Deferred revenue $ 503,298 $ (65,818 ) $ 437,480 Retained earnings $ 1,601,583 $ (17,900 ) $ 1,583,683 The table that follows presents the disaggregated revenues for the periods indicated (in thousands): For the Three Months Ended March 31, 2018 Segments Index Analytics All Other Total Product Types Recurring subscriptions $ 113,205 $ 118,244 $ 29,367 $ 260,815 Asset-based fees 85,483 — — 85,483 Non-recurring 3,226 744 1,048 5,018 Total $ 201,913 $ 118,987 $ 30,415 $ 351,316 MSCI’s policy for the majority of its subscription services is to bill in advance of services being provided and before the service period has begun. Under ASC 606, both the cash received and/or the amount billed in advance of the service period or the services being provided is presented as deferred revenue. Contract assets are services provided in advance of the payment due and are typically recorded as unbilled revenue. Since MSCI’s contracts are non-refundable and non-cancellable by the client, MSCI has an unconditional right to receive the cash for service and products provided in advance of billing and therefore are classified as “Accounts receivable” on the Company’s Unaudited Condensed Consolidated Statement of Financial Condition. This represents a change from past practice as a receivable was not recorded until the subscription period began and, as such, the adoption of ASC 606 resulted in a significant increase to both “Accounts receivable” and “Deferred revenue” with no change to net assets. March 31, 2018 Accounts receivable Deferred revenue Opening (1/1/2018) $ 473,400 $ 494,591 Closing (03/31/2018) 462,577 503,298 Increase/(decrease) $ (10,823 ) $ 8,707 The amount of revenue recognized in the period that was included in the opening current deferred revenue, which reflects the contract liability amounts, was $221.5 million. The difference between the opening and closing balances of the Company’s deferred revenue represents the increase in the balance as a result of billings offset by the amortization of deferred revenue to operating revenues. MSCI had an insignificant long-term deferred revenue balance as of March 31, 2018 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 chosen to use the practical expedient available under the new revenue standard and, as such, 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 is $397.4 million, which is expected to be recognized as follows: • Approximately $218.4 million of the remaining performance obligations over the next 12 month period; • Approximately $118.7 million of the remaining performance obligations over the second 12 month period; • Approximately $42.5 million of the remaining performance obligations over the third 12 month period; and • The remaining $17.8 million recognized in the periods thereafter.

Earnings Per Common Share

Earnings Per Common Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Common Share	4. EARNINGS PER COMMON SHARE Basic earnings per share (“EPS”) is computed by dividing income available to MSCI common shareholders 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 March 31, 2018 2017 (in thousands, except per share data) Net income $ 115,092 $ 72,951 Basic weighted average common shares outstanding 90,075 90,708 Effect of dilutive securities: Stock options and restricted stock units 2,512 916 Diluted weighted average common shares outstanding 92,587 91,624 Earnings per basic common share $ 1.28 $ 0.80 Earnings per diluted common share $ 1.24 $ 0.80

Property, Equipment and Leaseho

Property, Equipment and Leasehold Improvements	3 Months Ended
	Mar. 31, 2018
Property Plant And Equipment [Abstract]
Property, Equipment and Leasehold Improvements	5. PROPERTY, EQUIPMENT AND LEASEHOLD IMPROVEMENTS Property, equipment and leasehold improvements at March 31, 2018 and December 31, 2017 consisted of the following: As of March 31, December 31, 2018 2017 (in thousands) Computer & related equipment $ 200,255 $ 200,592 Furniture & fixtures 10,858 10,591 Leasehold improvements 51,983 51,128 Work-in-process 776 3,406 Subtotal 263,872 265,717 Accumulated depreciation and amortization (177,562 ) (171,280 ) Property, equipment and leasehold improvements, net $ 86,310 $ 94,437 Depreciation and amortization expense of property, equipment and leasehold improvements was $8.2 million and $8.8 million for the three months ended March 31, 2018 and 2017, respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	6. GOODWILL AND INTANGIBLE ASSETS Goodwill The following table presents goodwill by reportable segment: (in thousands) Index Analytics All Other (1) Total Goodwill at December 31, 2017 $ 1,205,400 $ 302,611 $ 52,610 $ 1,560,621 Foreign exchange translation adjustment 1,261 — 778 2,039 Goodwill at March 31, 2018 $ 1,206,661 $ 302,611 $ 53,388 $ 1,562,660 (1) Intangible Assets Amortization expense related to intangible assets was $11.3 million for both the three months ended March 31, 2018 and 2017. The amortization expense of acquired intangible assets was $9.2 million and $10.5 million for the three months ended March 31, 2018 and 2017, respectively. The amortization expense of internally developed capitalized software was $2.1 million and $0.8 million for the three months ended March 31, 2018 and 2017, respectively. The gross carrying and accumulated amortization amounts related to the Company’s identifiable intangible assets were as follows: As of March 31, December 31, 2018 2017 (in thousands) Gross intangible assets: Customer relationships $ 361,199 $ 361,199 Trademarks/trade names 223,382 223,382 Technology/software 229,654 225,407 Proprietary data 28,627 28,627 Subtotal 842,862 838,615 Foreign exchange translation adjustment (6,963 ) (9,167 ) Total gross intangible assets $ 835,899 $ 829,448 Accumulated amortization: Customer relationships $ (194,614 ) $ (189,100 ) Trademarks/trade names (119,618 ) (116,691 ) Technology/software (195,491 ) (193,095 ) Proprietary data (10,832 ) (10,352 ) Subtotal (520,555 ) (509,238 ) Foreign exchange translation adjustment 915 1,626 Total accumulated amortization $ (519,640 ) $ (507,612 ) Net intangible assets: Customer relationships $ 166,585 $ 172,099 Trademarks/trade names 103,764 106,691 Technology/software 34,163 32,312 Proprietary data 17,795 18,275 Subtotal 322,307 329,377 Foreign exchange translation adjustment (6,048 ) (7,541 ) Total net intangible assets $ 316,259 $ 321,836 The following table presents the estimated amortization expense for the remainder of the year ending December 31, 2018 and succeeding years: Years Ending December 31, Amortization Expense (in thousands) Remainder 2018 $ 35,050 2019 44,829 2020 42,992 2021 39,467 2022 36,496 Thereafter 117,425 Total $ 316,259

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
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. Leases. The Company leases facilities under non-cancelable operating lease agreements. The terms of certain lease agreements provide for rental payments on a graduated basis. The Company recognizes rent expense on the straight-line basis over the lease period and has accrued for rent expense incurred but not paid. Rent expense for the three months ended March 31, 2018 and 2017 was $6.3 million and $5.8 million, respectively. Senior Notes. The Company has issued an aggregate of $2.1 billion in senior unsecured notes (collectively, the “Senior Notes”) in the three discrete private offerings described below. On November 20, 2014, the Company completed its private offering of $800.0 million aggregate principal amount of 5.25% senior unsecured notes due 2024 (the “2024 Senior Notes”). The Company used the net proceeds from the offering of the 2024 Senior Notes, together with cash on hand, to repay in full its then outstanding term loan indebtedness of $794.8 million. On August 13, 2015, the Company completed its private offering of $800.0 million aggregate principal amount of 5.75% senior unsecured notes due 2025 (the “2025 Senior Notes”). The $789.5 million of net proceeds from the offering of the 2025 Senior Notes were allocated for general corporate purposes. On August 4, 2016, the Company completed its private offering of $500.0 million aggregate principal amount of 4.75% senior unsecured notes due 2026 (the “2026 Senior Notes”). The $493.3 million of net proceeds from the offering of the 2026 Senior Notes were allocated for general corporate purposes, including, without limitation, buybacks of its common stock and potential acquisitions. 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 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. At any time prior to August 15, 2018, the Company may use the proceeds of certain equity offerings to redeem up to 35% of the aggregate principal amount of the 2025 Senior Notes, including any permitted additional notes, at a redemption price equal to 105.75% of the principal amount. 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. At any time prior to August 1, 2019, the Company may use the proceeds of certain equity offerings to redeem up to 35% of the aggregate principal amount of the 2026 Senior Notes, including any permitted additional notes, at a redemption price equal to 104.75% of the principal amount. Interest payments attributable to the 2024 Senior Notes are due on May 15 th th th th st st Revolver. On November 20, 2014, the Company entered into a $200.0 million senior unsecured revolving credit agreement (the “2014 Revolving Credit Agreement”) with a syndicate of banks. The 2014 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 “Amendment”) to the 2014 Revolving Credit Agreement (the 2014 Revolving Credit Agreement as so amended, the “Revolving Credit Agreement”). The 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. At March 31, 2018, the Revolving Credit Agreement was undrawn. Long-term debt at March 31, 2018 was $2,078.8 million, net of $21.2 million in deferred financing fees. Long-term debt at December 31, 2017 was $2,078.1 million, net of $21.9 million in deferred financing fees. In connection with the closings of the Senior Notes offerings and entry into the 2014 Revolving Credit Agreement and the Amendment, the Company paid certain fees which, together with the existing fees related to prior credit facilities, are being amortized over their related lives. At March 31, 2018, $22.9 million of the deferred financing fees remain unamortized, $0.5 million of which is included in “Prepaid and other assets,” $1.2 million of which is included in “Other non-current assets” and $21.2 million of which is grouped and presented as part of “Long-term debt” on the Unaudited Condensed Consolidated Statement of Financial Condition. At March 31, 2018 and December 31, 2017, the fair market value of the Company’s debt obligations was $2,152.4 million and $2,231.1 million, respectively. The fair market value 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.

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Shareholders' Equity	8. SHAREHOLDERS’ EQUITY Return of capital . On October 28, 2015, the Board of Directors approved a stock repurchase program authorizing the purchase of up to $1.0 billion worth of shares of MSCI’s common stock (the “2015 Repurchase Program”). On October 26, 2016, the Board of Directors approved an additional stock repurchase program authorizing the purchase of up to $750.0 million worth of shares of the Company’s common stock (together with the $330.3 million remaining authorization under the 2015 Repurchase Program, the “2016 Repurchase Program”). Share repurchases made pursuant to the 2016 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 March 31, 2018, there was $664.7 million of available authorization remaining under the 2016 Repurchase Program. The following table provides information with respect to repurchases of the Company’s common stock made on the open market: Three Months Ended Average Price Paid Per Share Total Number of Shares Repurchased Dollar Value of Shares Repurchased (in thousands) March 31, 2018 $ 138.86 492 $ 68,345 March 31, 2017 $ 82.25 1,079 $ 88,744 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 Deferred 2018 Three Months Ended March 31, 0.38 34,848 34,900 (52 ) Total $ 0.38 $ 34,848 $ 34,900 $ (52 ) 2017 Three Months Ended March 31, 0.28 25,769 25,500 269 Total $ 0.28 $ 25,769 $ 25,500 $ 269 Common Stock. The following table presents activity related to shares of common stock issued and repurchased during the three months ended March 31, 2018: Common Stock Treasury Common Stock Issued Stock Outstanding Balance At December 31, 2017 129,543,856 (39,438,971 ) 90,104,885 Dividend payable/paid 111 (111 ) — Common stock issued and exercise of stock options 409,794 — 409,794 Shares withheld for tax withholding and exercises — (162,846 ) (162,846 ) Shares repurchased under stock repurchase programs — (492,175 ) (492,175 ) Shares issued to directors — — — Balance At March 31, 2018 129,953,761 (40,094,103 ) 89,859,658

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	9. INCOME TAXES The Company’s provision for income taxes was $24.3 million and $28.7 million for the three months ended March 31, 2018 and 2017, respectively. These amounts reflect effective tax rates of 17.5% and 28.2% for the three months ended March 31, 2018 and 2017, respectively. The decrease in the provision for income taxes and in the effective tax rate was primarily driven by Tax Reform as well as the impact of higher net discrete benefits. The effective tax rate of 17.5% for the three months ended March 31, 2018 reflects the Company’s estimate of the effective tax rate for the period and was impacted by certain net discrete items totaling $7.9 million, primarily related to $7.5 million of excess tax benefits on share-based compensation recognized during the period, which decreased the Company’s effective tax rate by 5.7 percentage points. On December 22, 2017, the U.S. government enacted Tax Reform which significantly revises the U.S. corporate income tax by, among other things, lowering U.S. corporate income tax rates, implementing a territorial tax system and imposing a one-time tax on deemed repatriation of historic earnings and profits of foreign subsidiaries (the “Toll Charge”). The U.S. federal income tax rate reduction was effective as of January 1, 2018. The Company’s provisional accounting for the effects of Tax Reform resulted in a net adjustment benefit of $1.6 million in the provision for income taxes for MSCI in the three months ended March 31, 2018 that primarily related to a change in the estimate of taxes on the amount of historical profits that were previously deemed to be permanently invested overseas. The cumulative accrual for Tax Reform as of March 31, 2018, including the charges recognized in the year ended December 31, 2017 and in the three months ended March 31, 2018, totals $32.9 million. Pursuant to SAB 118 and given the amount and complexity of the changes in tax law resulting from Tax Reform, the Company has not finalized the accounting for the income tax effects of Tax Reform. This includes the provisional amounts recorded related to the Toll Charge, the remeasurement of deferred taxes and the change in the Company’s indefinite reinvestment assertion. The impact of Tax Reform may differ from this estimate, possibly materially, during the defined one-year measurement period due to, among other things, further refinement of the Company’s calculations as it completes its tax returns for the fiscal year ended December 31, 2017, changes in interpretations and assumptions the Company has made and ongoing guidance and accounting interpretations that may be issued as a result of Tax Reform. As of December 31, 2017, the Company no longer considers the earnings of its foreign subsidiaries to be indefinitely reinvested. However, the Company is continuing to assess its intentions related to its indefinite reinvestment assertion for future periods. 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 2005 through 2016. 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 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. It is reasonably possible that significant changes in the balance of unrecognized tax benefits may occur within the next 12 months. At this time, however, it is not possible to reasonably estimate the expected change to the total amount of unrecognized tax benefits and the impact on the effective tax rate over the next 12 months.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment Information	10. 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 certain transactions or adjustments 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. 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, headcount, sales targets, data center consumption and other relevant usage measures. Due to the integrated structure of our 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 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 environmental, social and governance (“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 and benchmarking offerings that provide real estate performance analysis for funds, investors and managers. Real Estate performance and risk analytics range from portfolio 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 March 31, 2018 2017 (in thousands) Operating revenues Index $ 201,913 $ 163,435 Analytics 118,987 112,420 All Other 30,415 25,352 Total $ 351,316 $ 301,207 The following table presents segment profitability and a reconciliation to net income for the periods indicated: Three Months Ended March 31, 2018 2017 (in thousands) Index Adjusted EBITDA $ 145,929 $ 115,677 Analytics Adjusted EBITDA 33,593 29,600 All Other Adjusted EBITDA 7,187 5,544 Total operating segment profitability 186,708 150,821 Amortization of intangible assets 11,338 11,251 Depreciation and amortization of property, equipment and leasehold improvements 8,205 8,838 Operating income 167,166 130,732 Other expense (income), net 27,728 29,107 Provision for income taxes 24,346 28,674 Net income $ 115,092 $ 72,951 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 March 31, 2018 2017 (in thousands) Revenues Americas: United States $ 164,835 $ 144,838 Other 14,884 11,654 Total Americas 179,718 156,492 Europe, the Middle East and Africa ("EMEA"): United Kingdom 52,933 47,025 Other 72,687 60,302 Total EMEA 125,620 107,327 Asia & Australia: Japan 15,182 12,826 Other 30,796 24,562 Total Asia & Australia 45,978 37,388 Total $ 351,316 $ 301,207 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 March 31, December 31, 2018 2017 (in thousands) Long-lived assets Americas: United States $ 1,836,563 $ 1,847,605 Other 1,617 1,685 Total Americas 1,838,180 1,849,290 EMEA: United Kingdom 97,400 94,782 Other 20,255 22,394 Total EMEA 117,655 117,176 Asia & Australia: Japan 422 432 Other 8,972 9,996 Total Asia & Australia 9,394 10,428 Total $ 1,965,229 $ 1,976,894

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	11. SUBSEQUENT EVENTS On April 9, 2018, MSCI completed the sale of FEA to Allegro Development Corporation and, as a result, the operating results of FEA will no longer be included in the Analytics financial statements after that date. FEA includes the energy and commodity analytics product and was previously included within the Analytics segment. The impact of this divestiture is not material to the Analytics segment and the Company as a whole. Subsequent to the three months ended March 31, 2018 and through May 2, 2018, the Company repurchased an additional 1.0 million shares of common stock at an average price of $148.58 per share for a total value of $141.7 million. 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 MSCI’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. On May 1, 2018, the Board of Directors declared a cash dividend of $0.38 per share for second quarter 2018. The second quarter 2018 dividend is payable on May 31, 2018 to shareholders of record as of the close of trading on May 18, 2018.

Introduction and Basis of Pre18

Introduction and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2018
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 Inc. and its subsidiaries and include all adjustments of a normal, recurring nature necessary to state fairly the financial condition as of March 31, 2018 and December 31, 2017, the results of operations and comprehensive income for the three months ended March 31, 2018 and 2017 and cash flows for the three months ended March 31, 2018 and 2017. The unaudited condensed consolidated statement of financial condition and related financial statement information as of December 31, 2017 have been derived from the 2017 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, 2017. 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 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. Certain prior period amounts have been reclassified to conform to the current period presentation.
Concentrations	Concentrations For the three months ended March 31, 2018 and 2017, BlackRock, Inc. accounted for 12.9% and 10.3% of the Company’s consolidated operating revenues, respectively. For the three months ended March 31, 2018 and 2017, BlackRock, Inc. accounted for 22.1% and 18.6% of the Index segment operating revenues, respectively. No single customer represented 10.0% or more of revenues within the Analytics and All Other segments for the three months ended March 31, 2018 and 2017.
Recent Accounting Standards Updates	2. RECENT ACCOUNTING STANDARDS UPDATES In May 2014, the FASB issued Accounting Standards Update 2014-09, “ Revenue from Contracts with Customers (Topic 606) In March 2016, the FASB issued Accounting Standards Update 2016-08, “ Principal Versus Agent Considerations (Reporting Revenue Gross Versus Net) Identifying Performance Obligations and Licensing Narrow-Scope Improvements and Practical Expedients Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers In February 2016, the FASB issued Accounting Standards Update No. 2016-02, “ Leases (Topic 842) In June 2016, the FASB issued Accounting Standards Update No. 2016-13, “ Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In January 2017, the FASB issued Accounting Standards Update No. 2017-01, “ Business Combinations (Topic 805): Clarifying the Definition of a Business In January 2017, the FASB issued Accounting Standards Update No. 2017-04, “ Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In February 2017, the FASB issued Accounting Standards Update No. 2017-07, “ Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost In May 2017, the FASB issued Accounting Standards Update No. 2017-09, “ Compensation—Stock Compensation (Topic 718), Scope of Modification Accounting, Compensation—Stock Compensation Compensation—Stock Compensation In August 2017, the FASB issued Accounting Standards Update (“ASU”) No. 2017-12, “ Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, On December 22, 2017, the U.S. government enacted comprehensive tax legislation, the Tax Cuts and Jobs Act (“Tax Reform”). Given the significance of the legislation, the SEC staff issued Staff Accounting Bulletin No. 118, “ Income Tax Accounting Implications of the Tax Cuts and Jobs Act,

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 31, 2018
Disaggregation of Revenue	The table that follows presents the disaggregated revenues for the periods indicated (in thousands): For the Three Months Ended March 31, 2018 Segments Index Analytics All Other Total Product Types Recurring subscriptions $ 113,205 $ 118,244 $ 29,367 $ 260,815 Asset-based fees 85,483 — — 85,483 Non-recurring 3,226 744 1,048 5,018 Total $ 201,913 $ 118,987 $ 30,415 $ 351,316
Accounting Standards Update 2014-09 [Member]
Cumulative Impact of Adoption on Company’s Unaudited Condensed Consolidated Statement of Financial Condition	The cumulative impact of adoption on the Company’s Unaudited Condensed Consolidated Statement of Financial Condition was as follows (in thousands): Selected line items As reported at December 31, 2017 Adjustments due to Adoption of ASC 606 Adjusted as of December 31, 2017 Statement of Financial Condition Accounts receivable $ 327,597 $ 145,803 $ 473,400 Income taxes payable $ 14,828 $ 4,314 $ 19,142 Other accrued liabilities $ 85,710 $ 5,128 $ 90,838 Deferred revenue $ 374,365 $ 120,226 $ 494,591 Retained earnings $ 1,505,204 $ 16,135 $ 1,521,339
Schedule of Impact of Adopting New Standard on Company's Unaudited Condensed Consolidated Statement of Income and Statement of Financial Condition	The impact of adopting the new revenue standard on the Company’s Unaudited Condensed Consolidated Statement of Income through the date of March 31, 2018 is as follows (in thousands): For the period ended March 31, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Income Operating revenues $ 351,316 $ (2,286 ) $ 349,030 Operating income $ 167,166 $ (2,286 ) $ 164,880 Income before provision for income taxes $ 139,438 $ (2,286 ) $ 137,152 Provision for income taxes $ 24,346 $ 457 $ 24,803 Net income $ 115,092 $ (1,829 ) $ 113,263 Earnings per basic common share $ 1.28 $ (0.02 ) $ 1.26 Earnings per diluted common share $ 1.24 $ (0.02 ) $ 1.22 The impact of adopting the new revenue standard on the Company’s Unaudited Statement of Financial Condition through the date of March 31, 2018 is as follows (in thousands): March 31, 2018 Selected line items As reported at March 31, 2018 Impact of Change Without Adoption of ASC 606 Statement of Financial Condition Accounts receivable $ 462,577 $ (91,945 ) $ 370,632 Income taxes payable $ 22,144 $ (4,771 ) $ 17,373 Other accrued liabilities $ 83,106 $ (3,456 ) $ 79,650 Deferred revenue $ 503,298 $ (65,818 ) $ 437,480 Retained earnings $ 1,601,583 $ (17,900 ) $ 1,583,683
Schedule of Accounts Receivable and Deferred Revenue	March 31, 2018 Accounts receivable Deferred revenue Opening (1/1/2018) $ 473,400 $ 494,591 Closing (03/31/2018) 462,577 503,298 Increase/(decrease) $ (10,823 ) $ 8,707

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Computation of Basic and Diluted EPS	The following table presents the computation of basic and diluted EPS: Three Months Ended March 31, 2018 2017 (in thousands, except per share data) Net income $ 115,092 $ 72,951 Basic weighted average common shares outstanding 90,075 90,708 Effect of dilutive securities: Stock options and restricted stock units 2,512 916 Diluted weighted average common shares outstanding 92,587 91,624 Earnings per basic common share $ 1.28 $ 0.80 Earnings per diluted common share $ 1.24 $ 0.80

Property, Equipment and Lease21

Property, Equipment and Leasehold Improvements (Tables)	3 Months Ended
	Mar. 31, 2018
Property Plant And Equipment [Abstract]
Schedule of Property, Equipment and Leasehold Improvements	Property, equipment and leasehold improvements at March 31, 2018 and December 31, 2017 consisted of the following: As of March 31, December 31, 2018 2017 (in thousands) Computer & related equipment $ 200,255 $ 200,592 Furniture & fixtures 10,858 10,591 Leasehold improvements 51,983 51,128 Work-in-process 776 3,406 Subtotal 263,872 265,717 Accumulated depreciation and amortization (177,562 ) (171,280 ) Property, equipment and leasehold improvements, net $ 86,310 $ 94,437

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2018
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 (1) Total Goodwill at December 31, 2017 $ 1,205,400 $ 302,611 $ 52,610 $ 1,560,621 Foreign exchange translation adjustment 1,261 — 778 2,039 Goodwill at March 31, 2018 $ 1,206,661 $ 302,611 $ 53,388 $ 1,562,660 (1)
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 March 31, December 31, 2018 2017 (in thousands) Gross intangible assets: Customer relationships $ 361,199 $ 361,199 Trademarks/trade names 223,382 223,382 Technology/software 229,654 225,407 Proprietary data 28,627 28,627 Subtotal 842,862 838,615 Foreign exchange translation adjustment (6,963 ) (9,167 ) Total gross intangible assets $ 835,899 $ 829,448 Accumulated amortization: Customer relationships $ (194,614 ) $ (189,100 ) Trademarks/trade names (119,618 ) (116,691 ) Technology/software (195,491 ) (193,095 ) Proprietary data (10,832 ) (10,352 ) Subtotal (520,555 ) (509,238 ) Foreign exchange translation adjustment 915 1,626 Total accumulated amortization $ (519,640 ) $ (507,612 ) Net intangible assets: Customer relationships $ 166,585 $ 172,099 Trademarks/trade names 103,764 106,691 Technology/software 34,163 32,312 Proprietary data 17,795 18,275 Subtotal 322,307 329,377 Foreign exchange translation adjustment (6,048 ) (7,541 ) Total net intangible assets $ 316,259 $ 321,836
Estimated Amortization Expense for Remainder of 2018 and Succeeding Years	The following table presents the estimated amortization expense for the remainder of the year ending December 31, 2018 and succeeding years: Years Ending December 31, Amortization Expense (in thousands) Remainder 2018 $ 35,050 2019 44,829 2020 42,992 2021 39,467 2022 36,496 Thereafter 117,425 Total $ 316,259

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2018
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: Three Months Ended Average Price Paid Per Share Total Number of Shares Repurchased Dollar Value of Shares Repurchased (in thousands) March 31, 2018 $ 138.86 492 $ 68,345 March 31, 2017 $ 82.25 1,079 $ 88,744
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 Deferred 2018 Three Months Ended March 31, 0.38 34,848 34,900 (52 ) Total $ 0.38 $ 34,848 $ 34,900 $ (52 ) 2017 Three Months Ended March 31, 0.28 25,769 25,500 269 Total $ 0.28 $ 25,769 $ 25,500 $ 269
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 three months ended March 31, 2018: Common Stock Treasury Common Stock Issued Stock Outstanding Balance At December 31, 2017 129,543,856 (39,438,971 ) 90,104,885 Dividend payable/paid 111 (111 ) — Common stock issued and exercise of stock options 409,794 — 409,794 Shares withheld for tax withholding and exercises — (162,846 ) (162,846 ) Shares repurchased under stock repurchase programs — (492,175 ) (492,175 ) Shares issued to directors — — — Balance At March 31, 2018 129,953,761 (40,094,103 ) 89,859,658

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Operating Revenue by Reportable Segment	The following table presents operating revenue by reportable segment for the periods indicated: Three Months Ended March 31, 2018 2017 (in thousands) Operating revenues Index $ 201,913 $ 163,435 Analytics 118,987 112,420 All Other 30,415 25,352 Total $ 351,316 $ 301,207
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 March 31, 2018 2017 (in thousands) Index Adjusted EBITDA $ 145,929 $ 115,677 Analytics Adjusted EBITDA 33,593 29,600 All Other Adjusted EBITDA 7,187 5,544 Total operating segment profitability 186,708 150,821 Amortization of intangible assets 11,338 11,251 Depreciation and amortization of property, equipment and leasehold improvements 8,205 8,838 Operating income 167,166 130,732 Other expense (income), net 27,728 29,107 Provision for income taxes 24,346 28,674 Net income $ 115,092 $ 72,951
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 March 31, 2018 2017 (in thousands) Revenues Americas: United States $ 164,835 $ 144,838 Other 14,884 11,654 Total Americas 179,718 156,492 Europe, the Middle East and Africa ("EMEA"): United Kingdom 52,933 47,025 Other 72,687 60,302 Total EMEA 125,620 107,327 Asia & Australia: Japan 15,182 12,826 Other 30,796 24,562 Total Asia & Australia 45,978 37,388 Total $ 351,316 $ 301,207
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 March 31, December 31, 2018 2017 (in thousands) Long-lived assets Americas: United States $ 1,836,563 $ 1,847,605 Other 1,617 1,685 Total Americas 1,838,180 1,849,290 EMEA: United Kingdom 97,400 94,782 Other 20,255 22,394 Total EMEA 117,655 117,176 Asia & Australia: Japan 422 432 Other 8,972 9,996 Total Asia & Australia 9,394 10,428 Total $ 1,965,229 $ 1,976,894

Introduction and Basis of Pre25

Introduction and Basis of Presentation - Additional Information (Detail) - Operating Revenues [Member] - Customer Concentration Risk [Member] - Customer	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
BlackRock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	12.90%	10.30%
Index [Member] | BlackRock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	22.10%	18.60%
Analytics [Member]
Introduction And Basis Of Presentation [Line Items]
Number of major customers represented 10.0% or more of revenues	0	0
All Other [Member]
Introduction And Basis Of Presentation [Line Items]
Number of major customers represented 10.0% or more of revenues	0	0

Recent Accounting Standards U26

Recent Accounting Standards Updates - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)
New Accounting Pronouncements And Changes In Accounting Principles [Abstract]
Non-service related pension costs	$ 0.1

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Revenue Recognition [Line Items]
Revenue, performance obligation satisfied at point in time, transfer of control, description	With respect to software licenses for the Company’s energy and commodity analytics products, MSCI’s performance obligation is partially satisfied and revenue recognized at the point in time when the software’s code key is delivered to the customer, which based upon a fair value assessment, represents approximately 80.0% of the contract value. MSCI’s remaining performance obligations are the post contractual support services and revenue is recognized evenly over the course of the license term.
Percentage of value of software and remaining performance obligation	82.00%
Revenue, performance obligations and revenue recognition, description	The majority of MSCI’s contracts have a duration of one year or less and, accordingly, revenue associated with these performance obligations will be recognized within 12 months.
Revenue recognized during period included in deferred revenue	$ 221.5
Accounting Standards Update 2014-09 [Member] | Adjustments due to Adoption of ASC 606 [Member]
Revenue Recognition [Line Items]
Increase to accounts receivable and deferred revenue	$ 135.5

Revenue Recognition - Cumulativ

Revenue Recognition - Cumulative Impact of Adoption on Company's Unaudited Condensed Consolidated Statement of Financial Condition (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable	$ 462,577		$ 327,597
Income taxes payable	22,144		14,828
Other accrued liabilities	83,106		85,710
Deferred revenue	503,298		374,365
Retained earnings	1,601,583		1,505,204
Accounting Standards Update 2014-09 [Member]
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable		$ 473,400	473,400
Income taxes payable			19,142
Other accrued liabilities			90,838
Deferred revenue		$ 494,591	494,591
Retained earnings			1,521,339
Accounting Standards Update 2014-09 [Member] | Adjustments due to Adoption of ASC 606 [Member]
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable	(91,945)		145,803
Income taxes payable	(4,771)		4,314
Other accrued liabilities	(3,456)		5,128
Deferred revenue	(65,818)		120,226
Retained earnings	$ (17,900)		$ 16,135

Revenue Recognition - Schedule

Revenue Recognition - Schedule of Impact of Adopting New Revenue Standard on Company's Unaudited Condensed Consolidated Statement of Income (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Income
Operating revenues	$ 351,316	$ 301,207
Operating income	167,166	130,732
Income before provision for income taxes	139,438	101,625
Provision for income taxes	24,346	28,674
Net income	$ 115,092	$ 72,951
Earnings per basic common share	$ 1.28	$ 0.80
Earnings per diluted common share	$ 1.24	$ 0.80
Accounting Standards Update 2014-09 [Member] | Impact of Change [Member]
Statement of Income
Operating revenues	$ (2,286)
Operating income	(2,286)
Income before provision for income taxes	(2,286)
Provision for income taxes	457
Net income	$ (1,829)
Earnings per basic common share	$ (0.02)
Earnings per diluted common share	$ (0.02)
Accounting Standards Update 2014-09 [Member] | Without Adoption of ASC 606 [Member]
Statement of Income
Operating revenues	$ 349,030
Operating income	164,880
Income before provision for income taxes	137,152
Provision for income taxes	24,803
Net income	$ 113,263
Earnings per basic common share	$ 1.26
Earnings per diluted common share	$ 1.22

Revenue Recognition - Schedul30

Revenue Recognition - Schedule of Impact of Adopting New Revenue Standard on Company's Unaudited Statement of Financial Condition (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Statement of Financial Condition
Accounts receivable	$ 462,577		$ 327,597
Income taxes payable	22,144		14,828
Other accrued liabilities	83,106		85,710
Deferred revenue	503,298		374,365
Retained earnings	1,601,583		1,505,204
Accounting Standards Update 2014-09 [Member]
Statement of Financial Condition
Accounts receivable		$ 473,400	473,400
Income taxes payable			19,142
Other accrued liabilities			90,838
Deferred revenue		$ 494,591	494,591
Retained earnings			1,521,339
Accounting Standards Update 2014-09 [Member] | Impact of Change [Member]
Statement of Financial Condition
Accounts receivable	(91,945)		145,803
Income taxes payable	(4,771)		4,314
Other accrued liabilities	(3,456)		5,128
Deferred revenue	(65,818)		120,226
Retained earnings	(17,900)		$ 16,135
Accounting Standards Update 2014-09 [Member] | Without Adoption of ASC 606 [Member]
Statement of Financial Condition
Accounts receivable	370,632
Income taxes payable	17,373
Other accrued liabilities	79,650
Deferred revenue	437,480
Retained earnings	$ 1,583,683

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 351,316
Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	201,913
Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	118,987
All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	30,415
Recurring Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	260,815
Recurring Subscriptions [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	113,205
Recurring Subscriptions [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	118,244
Recurring Subscriptions [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	29,367
Asset-based Fees [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	85,483
Asset-based Fees [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	85,483
Non-recurring [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	5,018
Non-recurring [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	3,226
Non-recurring [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	744
Non-recurring [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 1,048

Revenue Recognition - Schedul32

Revenue Recognition - Schedule of Accounts Receivable and Deferred Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017
Revenue Recognition [Line Items]
Accounts receivable	$ 462,577			$ 327,597
Accounts receivable, Increase/(decrease)	134,801	$ 40,582
Deferred revenue	503,298			374,365
Deferred revenue	148,468	$ 43,247
Accounting Standards Update 2014-09 [Member]
Revenue Recognition [Line Items]
Accounts receivable			$ 473,400	473,400
Deferred revenue			$ 494,591	494,591
Accounting Standards Update 2014-09 [Member] | Adjustments due to Adoption of ASC 606 [Member]
Revenue Recognition [Line Items]
Accounts receivable	(91,945)			145,803
Accounts receivable, Increase/(decrease)	(10,823)
Deferred revenue	(65,818)			$ 120,226
Deferred revenue	$ 8,707

Revenue Recognition - Additio33

Revenue Recognition - Additional Information (Detail 1) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2018-04-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 218.4
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-04-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 118.7
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-04-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 42.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-04-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 17.8
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Contract with One Year or More [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2018-01-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 397.4

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
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Net income	$ 115,092	$ 72,951
Basic weighted average common shares outstanding	90,075	90,708
Effect of dilutive securities:
Stock options and restricted stock units	2,512	916
Diluted weighted average common shares outstanding	92,587	91,624
Earnings per basic common share	$ 1.28	$ 0.80
Earnings per diluted common share	$ 1.24	$ 0.80

Property, Equipment and Lease35

Property, Equipment and Leasehold Improvements - Schedule of Property, Equipment and Leasehold Improvements (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Abstract]
Computer & related equipment	$ 200,255	$ 200,592
Furniture & fixtures	10,858	10,591
Leasehold improvements	51,983	51,128
Work-in-process	776	3,406
Subtotal	263,872	265,717
Accumulated depreciation and amortization	(177,562)	(171,280)
Property, equipment and leasehold improvements, net	$ 86,310	$ 94,437

Property, Equipment and Lease36

Property, Equipment and Leasehold Improvements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Property Plant And Equipment [Abstract]
Depreciation and amortization of property, equipment and leasehold improvements	$ 8,205	$ 8,838

Goodwill and Intangible Asset37

Goodwill and Intangible Assets - Schedule of Goodwill by Reportable Segment (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Goodwill [Line Items]
Goodwill, Beginning balance	$ 1,560,621
Foreign exchange translation adjustment	2,039
Goodwill, Ending balance	1,562,660
Index [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	1,205,400
Foreign exchange translation adjustment	1,261
Goodwill, Ending balance	1,206,661
Analytics [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	302,611
Goodwill, Ending balance	302,611
All Other [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	52,610
Foreign exchange translation adjustment	778
Goodwill, Ending balance	$ 53,388

Goodwill and Intangible Asset38

Goodwill and Intangible Assets - Schedule of Goodwill by Reportable Segment - Parenthetical (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 1,562,660	$ 1,560,621
All Other [Member]
Goodwill [Line Items]
Goodwill	53,388	52,610
All Other [Member] | ESG [Member]
Goodwill [Line Items]
Goodwill	31,600	31,600
All Other [Member] | Real Estate [Member]
Goodwill [Line Items]
Goodwill	$ 21,800	$ 21,000

Goodwill and Intangible Asset39

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Goodwill [Line Items]
Amortization of intangible assets	$ 11,338	$ 11,251
Acquired Intangible Assets [Member]
Goodwill [Line Items]
Amortization of intangible assets	9,200	10,500
Capitalized Software [Member]
Goodwill [Line Items]
Amortization of intangible assets	$ 2,100	$ 800

Goodwill and Intangible Asset40

Goodwill and Intangible Assets - Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Identifiable Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	$ 835,899	$ 829,448
Accumulated amortization	(519,640)	(507,612)
Net carrying value	316,259	321,836
Customer Relationships [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	361,199	361,199
Accumulated amortization	(194,614)	(189,100)
Net carrying value	166,585	172,099
Trademarks/Trade Names [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	223,382	223,382
Accumulated amortization	(119,618)	(116,691)
Net carrying value	103,764	106,691
Technology/Software [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	229,654	225,407
Accumulated amortization	(195,491)	(193,095)
Net carrying value	34,163	32,312
Proprietary Data [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	28,627	28,627
Accumulated amortization	(10,832)	(10,352)
Net carrying value	17,795	18,275
Subtotal [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	842,862	838,615
Accumulated amortization	(520,555)	(509,238)
Net carrying value	322,307	329,377
Foreign Exchange Translation Adjustment [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	(6,963)	(9,167)
Accumulated amortization	915	1,626
Net carrying value	$ (6,048)	$ (7,541)

Goodwill and Intangible Asset41

Goodwill and Intangible Assets - Estimated Amortization Expense for Remainder of 2018 and Succeeding Years (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Remainder 2,018	$ 35,050
2,019	44,829
2,020	42,992
2,021	39,467
2,022	36,496
Thereafter	117,425
Net carrying value	$ 316,259	$ 321,836

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	Aug. 04, 2016	Aug. 13, 2015	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Nov. 20, 2014
Schedule Of Commitments And Contingencies [Line Items]
Annual rent expense			$ 6,300,000	$ 5,800,000
Revolving credit agreement, conditional description			The 2014 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 “Amendment”) to the 2014 Revolving Credit Agreement (the 2014 Revolving Credit Agreement as so amended, the “Revolving Credit Agreement”). The 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.
Long-term debt			$ 2,078,816,000		$ 2,078,093,000
Deferred financing fees			21,200,000		21,900,000
Fair market value of debt obligations			2,152,400,000		$ 2,231,100,000
Prepaid and Other Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			500,000
Other Non-Current Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			1,200,000
Long-term Debt [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			$ 21,200,000
2014 Revolving Credit Agreement [Member]
Schedule Of Commitments And Contingencies [Line Items]
Revolving credit facility, maximum borrowing						$ 200,000,000
Revolving credit agreement, term			5 years
Revolving Credit Agreement [Member]
Schedule Of Commitments And Contingencies [Line Items]
Revolving credit facility, maximum borrowing	$ 220,000,000
Revolving credit agreement, extended term	1 year
Senior Notes [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount			$ 2,100,000,000
Senior Notes and Revolving Credit Facility [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees			$ 22,900,000
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.
Term Loan [Member]
Schedule Of Commitments And Contingencies [Line Items]
Outstanding indebtedness, amount						$ 794,800,000
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%
Net proceeds from borrowing		$ 789,500,000
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%
Net proceeds from borrowing	$ 493,300,000
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.
Percentage of aggregate principal amount redeemed			35.00%
Redemption price			104.75%
5.75% Senior Notes Due In 2025 [Member]
Schedule Of Commitments And Contingencies [Line Items]
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.
Percentage of aggregate principal amount redeemed			35.00%
Redemption price			105.75%

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Detail) - USD ($)	Mar. 31, 2018	Oct. 26, 2016	Oct. 28, 2015
2015 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase program authorizing the purchase of shares			$ 1,000,000,000
Stock repurchase program, remaining authorized repurchase amount		$ 330,300,000
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	$ 664,700,000

Shareholders' Equity - Schedule

Shareholders' Equity - Schedule of Company's Common Stock Repurchases Made on Open Market (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Equity, Class of Treasury Stock [Line Items]
Total Number of Shares Repurchased	492,175
Open Market Purchases of Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Average Price Paid Per Share	$ 138.86	$ 82.25
Total Number of Shares Repurchased	492,000	1,079,000
Dollar Value of Shares Repurchased	$ 68,345	$ 88,744

Shareholders' Equity - Schedu45

Shareholders' Equity - Schedule of Dividends Declared Per Common Share and Total Amounts Declared, Distributed and Deferred (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement Of Stockholders Equity [Abstract]
Dividend declared per common share	$ 0.38	$ 0.28
Cash dividends declared, Amount	$ 34,848	$ 25,769
Cash dividends distributed, Amount	34,900	25,500
Cash dividends deferred, Amount	$ (52)	$ 269

Shareholders' Equity - Summary

Shareholders' Equity - Summary of Activity Related to Shares of Common Stock Issued and Repurchased (Detail)	3 Months Ended
	Mar. 31, 2018shares
Common Stock Outstanding [Line Items]
Beginning balance	90,104,885
Common stock issued and exercise of stock options	409,794
Shares withheld for tax withholding and exercises	(162,846)
Shares repurchased under stock repurchase programs	(492,175)
Ending balance	89,859,658
Common Stock Issued [Member]
Common Stock Outstanding [Line Items]
Beginning balance	129,543,856
Dividend payable/paid	111
Common stock issued and exercise of stock options	409,794
Ending balance	129,953,761
Treasury Stock [Member]
Common Stock Outstanding [Line Items]
Beginning balance	(39,438,971)
Dividend payable/paid	(111)
Shares withheld for tax withholding and exercises	(162,846)
Shares repurchased under stock repurchase programs	(492,175)
Ending balance	(40,094,103)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Examination [Line Items]
Provision for income taxes	$ 24,346	$ 28,674
Effective tax rate	17.50%	28.20%
Amounts effect on effective tax rate	$ 7,900
Decrease in effective tax rate	5.70%
Net adjustment benefit	$ 1,600
Cumulative accrual of tax reform, including charge recognized	$ 32,900
Significant change in unrecognized tax benefits, reasonably possible	It is reasonably possible that significant changes in the balance of unrecognized tax benefits may occur within the next 12 months.
Significant change in unrecognized tax benefits, not possible	At this time, however, it is not possible to reasonably estimate the expected change to the total amount of unrecognized tax benefits and the impact on the effective tax rate over the next 12 months.
Minimum [Member]
Income Tax Examination [Line Items]
Tax years under examination	2,005
Maximum [Member]
Income Tax Examination [Line Items]
Tax years under examination	2,016
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	2,007
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	2,008
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Minimum [Member] | Morgan Stanley [Member]
Income Tax Examination [Line Items]
Tax years under examination	2,006
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Maximum [Member] | Morgan Stanley [Member]
Income Tax Examination [Line Items]
Tax years under examination	2,008
Accounting Standards Update 2016-09 [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member]
Income Tax Examination [Line Items]
Amount of excess tax benefits recognition	$ 7,500

Segment Information - Additiona

Segment Information - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2018Segment
Segment Reporting [Abstract]
Number of operating segments	4

Segment Information - Operating

Segment Information - Operating Revenue by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 351,316	$ 301,207
Index [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	201,913	163,435
Analytics [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	118,987	112,420
All Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 30,415	$ 25,352

Segment Information - Segment P

Segment Information - Segment Profitability and Reconciliation to Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 186,708	$ 150,821
Amortization of intangible assets	11,338	11,251
Depreciation and amortization of property, equipment and leasehold improvements	8,205	8,838
Operating income	167,166	130,732
Other expense (income), net	27,728	29,107
Provision for income taxes	24,346	28,674
Net income	115,092	72,951
Index [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	145,929	115,677
Analytics [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	33,593	29,600
All Other [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 7,187	$ 5,544

Segment Information - Revenue b

Segment Information - Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 351,316	$ 301,207
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	164,835	144,838
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	14,884	11,654
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	179,718	156,492
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	52,933	47,025
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	72,687	60,302
Europe, the Middle East and Africa ("EMEA") [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	125,620	107,327
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	15,182	12,826
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	30,796	24,562
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 45,978	$ 37,388

Segment Information - Long-Live

Segment Information - Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1,965,229	$ 1,976,894
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,836,563	1,847,605
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,617	1,685
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,838,180	1,849,290
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	97,400	94,782
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	20,255	22,394
Total EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	117,655	117,176
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	422	432
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	8,972	9,996
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 9,394	$ 10,428

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($)	May 01, 2018	Apr. 27, 2018	Mar. 31, 2018	Mar. 31, 2017	Oct. 26, 2016
Subsequent Event [Line Items]
Total Number of Shares Repurchased			492,175
Value of shares repurchased			$ 91,277,000	$ 100,362,000
Quarterly dividend declared			$ 0.38	$ 0.28
2016 Repurchase Program [Member]
Subsequent Event [Line Items]
Repurchase program authorizing the purchase of shares					$ 750,000,000
Stock repurchase program, remaining authorized repurchase amount			$ 664,700,000
Subsequent Events [Member]
Subsequent Event [Line Items]
Total Number of Shares Repurchased		1,000,000
Average Price Paid Per Share		$ 148.58
Value of shares repurchased		$ 141,700,000
Quarterly dividend declared	$ 0.38
Quarterly dividend declared date	May 1, 2018
Quarterly dividend payable date	May 31, 2018
Quarterly dividend record date	May 18, 2018
Subsequent Events [Member] | 2018 Repurchase Program [Member]
Subsequent Event [Line Items]
Repurchase program authorizing the purchase of shares	$ 1,000,000
Subsequent Events [Member] | 2016 Repurchase Program [Member]
Subsequent Event [Line Items]
Stock repurchase program, remaining authorized repurchase amount	$ 523,100,000