MSCI (MSCI) 10-Q 2 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 26, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
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 Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		88,032,852

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 1,398,398	$ 889,502
Accounts receivable (net of allowances of $1,700 and $1,700 at September 30, 2018 and December 31, 2017, respectively)	378,705	327,597
Prepaid income taxes	21,276	15,103
Prepaid and other assets	39,972	34,927
Assets held-for-sale	18,995
Total current assets	1,857,346	1,267,129
Property, equipment and leasehold improvements (net of accumulated depreciation and amortization of $178,618 and $171,280 at September 30, 2018 and December 31, 2017, respectively)	82,745	94,437
Goodwill	1,547,002	1,560,621
Intangible assets (net of accumulated amortization of $530,760 and $507,612 at September 30, 2018 and December 31, 2017, respectively)	287,445	321,836
Deferred tax assets	11,860	12,013
Other non-current assets	20,007	19,632
Total assets	3,806,405	3,275,668
Current liabilities:
Accounts payable	2,200	1,612
Income taxes payable	9,581	14,828
Accrued compensation and related benefits	109,823	131,156
Other accrued liabilities	106,328	85,710
Deferred revenue	441,884	374,365
Liabilities held-for-sale	5,234
Total current liabilities	675,050	607,671
Long-term debt	2,574,616	2,078,093
Deferred taxes	70,629	78,027
Other non-current liabilities	107,669	110,865
Total liabilities	3,427,964	2,874,656
Commitments and Contingencies (see Note 7 and Note 8)
Shareholders' equity:
Preferred stock (par value $0.01, 100,000,000 shares authorized; no shares issued)
Common stock (par value $0.01; 750,000,000 common shares authorized; 130,002,538 and 129,543,856 common shares issued and 88,593,329 and 90,104,885 common shares outstanding at September 30, 2018 and December 31, 2017, respectively)	1,300	1,295
Treasury shares, at cost (41,409,209 and 39,438,971 common shares held at September 30, 2018 and December 31, 2017, respectively)	(2,615,827)	(2,321,989)
Additional paid in capital	1,295,450	1,264,849
Retained earnings	1,755,727	1,505,204
Accumulated other comprehensive loss	(58,209)	(48,347)
Total shareholders' equity	378,441	401,012
Total liabilities and shareholders' equity	$ 3,806,405	$ 3,275,668

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 1,700	$ 1,700
Property, equipment and leasehold improvements, accumulated depreciation and amortization	178,618	171,280
Intangible assets, accumulated amortization	$ 530,760	$ 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	130,002,538	129,543,856
Common stock, shares outstanding	88,593,329	90,104,885
Treasury shares	41,409,209	39,438,971

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Operating revenues	$ 357,934	$ 322,097	$ 1,072,296	$ 939,393
Operating expenses:
Cost of revenues	70,906	68,433	213,578	204,434
Selling and marketing	46,149	44,873	139,974	129,395
Research and development	20,591	17,974	61,099	55,140
General and administrative	24,751	22,079	74,974	64,484
Amortization of intangible assets	11,681	10,614	42,556	32,987
Depreciation and amortization of property, equipment and leasehold improvements	7,453	9,325	23,035	27,322
Total operating expenses	181,531	173,298	555,216	513,762
Operating income	176,403	148,799	517,080	425,631
Interest income	(6,522)	(1,835)	(13,573)	(4,077)
Interest expense	35,902	29,020	97,223	87,071
Other expense (income)	177	811	(9,177)	2,698
Other expense (income), net	29,557	27,996	74,473	85,692
Income before provision for income taxes	146,846	120,803	442,607	339,939
Provision for income taxes	23,014	35,650	86,854	100,569
Net income	$ 123,832	$ 85,153	$ 355,753	$ 239,370
Earnings per basic common share	$ 1.39	$ 0.94	$ 3.98	$ 2.65
Earnings per diluted common share	$ 1.36	$ 0.93	$ 3.87	$ 2.61
Weighted average shares outstanding used in computing earnings per share
Basic	88,796	90,112	89,323	90,406
Diluted	91,372	91,868	91,843	91,731
Dividend declared per common share	$ 0.58	$ 0.38	$ 1.34	$ 0.94

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 123,832	$ 85,153	$ 355,753	$ 239,370
Other comprehensive (loss) income:
Foreign currency translation adjustments	(3,338)	3,458	(11,860)	11,362
Foreign currency translation adjustments, net	(3,338)	3,458	(11,860)	11,362
Pension and other post-retirement adjustments	22	(69)	116	(343)
Income tax effect	(10)	(106)	(55)	(366)
Pension and other post-retirement adjustments, net	12	(175)	61	(709)
Net investment hedge adjustments			1,937
Net investment hedge adjustments, net			1,937
Other comprehensive (loss) income, net of tax	(3,326)	3,283	(9,862)	10,653
Comprehensive income	$ 120,506	$ 88,436	$ 345,891	$ 250,023

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities
Net income	$ 355,753	$ 239,370
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	42,556	32,987
Stock-based compensation expense	27,942	27,668
Depreciation and amortization of property, equipment and leasehold improvements	23,035	27,322
Amortization of debt origination fees	2,730	2,547
Deferred taxes	(9,110)	(11,452)
Gain on divestitures, net of costs	(12,055)
Other non-cash adjustments	357	294
Changes in assets and liabilities:
Accounts receivable	(60,250)	(87,168)
Prepaid income taxes	(6,229)	4,605
Prepaid and other assets	(3,756)	(7,132)
Accounts payable	605	1,806
Accrued compensation and related benefits	(18,806)	(19,074)
Income taxes payable	(9,562)
Other accrued liabilities	21,157	756
Deferred revenue	89,730	38,932
Other	(4,510)	9,544
Net cash provided by operating activities	439,587	261,005
Cash flows from investing activities
Capital expenditures	(13,069)	(17,440)
Capitalized software development costs	(13,115)	(10,777)
Proceeds from the sale of capital equipment	10
Proceeds from divestitures	21,010
Proceeds from sale of investments		771
Net cash used in investing activities	(5,164)	(27,446)
Cash flows from financing activities
Proceeds from exercise of stock options	365	1,781
Repurchase of treasury shares	(292,970)	(150,350)
Payment of dividends	(120,533)	(85,306)
Proceeds from borrowings	500,000
Payment of debt issuance costs	(6,262)
Net cash provided by (used in) financing activities	80,600	(233,875)
Effect of exchange rate changes	(6,127)	7,497
Net increase in cash	508,896	7,181
Cash and cash equivalent, beginning of period	889,502	791,834
Cash and cash equivalent, end of period	1,398,398	799,015
Supplemental disclosure of cash flow information:
Cash paid for interest	91,503	91,264
Cash paid for income taxes	110,197	100,161
Supplemental disclosure of non-cash investing activities
Property, equipment and leasehold improvements accrued, but not yet paid	3,777	3,501
Supplemental disclosure of non-cash financing activities
Cash dividends declared, but not yet paid	$ 889	$ 900

Introduction and Basis of Prese

Introduction and Basis of Presentation	9 Months Ended
	Sep. 30, 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 (collectively, “content”), 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, except assets and liabilities held-for-sale associated with Investor Force Holdings, Inc. (“InvestorForce”), necessary to state fairly the financial condition as of September 30, 2018 and December 31, 2017, the results of operations and comprehensive income for the three and nine months ended September 30, 2018 and 2017 and cash flows for the nine months ended September 30, 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 nine months ended September 30, 2018 and 2017, BlackRock, Inc. accounted for 12.2% and 11.1% of the Company’s consolidated operating revenues, respectively. For the nine months ended September 30, 2018 and 2017, BlackRock, Inc. accounted for 20.7% and 19.6% 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 nine months ended September 30, 2018 and 2017.

Recent Accounting Standards Upd

Recent Accounting Standards Updates	9 Months Ended
	Sep. 30, 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 July 2018, the FASB issued Accounting Standards Update No. 2018-10, “ Codification Improvements to Topic 842, Leases, Targeted Improvements, The Company has reached a decision as to what system it will use to manage the accounting for leases, determined the contracts that would be considered leases under the new guidance and is currently in the process of implementing the system and establishing the appropriate controls and procedures. The Company will adopt the new lease standard as of January 1, 2019 using the optional transition method provided under ASU 2018-11 and is continuing to evaluate the potential impact that ASU 2016-02, ASU 2018-10 and ASU 2018-11 will have on its condensed consolidated financial statements. 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 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, In June 2018, the FASB issued Accounting Standards Update No. 2018-07, “ Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, In August 2018, the FASB issued Accounting Standards Update No. 2018-15, “ Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40) In August 2018, the SEC issued release number 33-10532, “ Disclosure Update and Simplification,

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 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 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 and usage-based royalty 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 or number of instruments. These fees are variable and fall within the sales and usage-based royalty 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 the fees for which are 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 to which the Company expects to be entitled 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 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. On April 9, 2018, MSCI completed its divestiture of Financial Engineering Associates, Inc. (“FEA”), its energy and commodity analytics product line. See Note 11, “Divestitures,” 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 is 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, where clients pay us for the right to have their logo on certain of our products, 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 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’s judgement ( e.g. MSCI has elected the Modified Retrospective Approach and, as such, applied the new revenue standard only to contracts that were not completed at the January 1, 2018 adoption date and did not adjust 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 since 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 September 30, 2018 is as follows (in thousands): For the Three Months ended September 30, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Income Operating revenues $ 357,934 $ (1,052 ) $ 356,882 Operating income $ 176,403 $ (1,052 ) $ 175,351 Income before provision for income taxes $ 146,846 $ (1,052 ) $ 145,794 Provision for income taxes $ 23,014 $ (210 ) $ 22,804 Net income $ 123,832 $ (842 ) $ 122,990 Earnings per basic common share $ 1.39 $ (0.01 ) $ 1.38 Earnings per diluted common share $ 1.36 $ (0.01 ) $ 1.35 For the Nine Months ended September 30, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Income Operating revenues $ 1,072,296 $ (5,502 ) $ 1,066,794 Operating income $ 517,080 $ (5,502 ) $ 511,578 Income before provision for income taxes $ 442,607 $ (5,502 ) $ 437,105 Provision for income taxes $ 86,854 $ (1,100 ) $ 85,754 Net income $ 355,753 $ (4,402 ) $ 351,351 Earnings per basic common share $ 3.98 $ (0.05 ) $ 3.93 Earnings per diluted common share $ 3.87 $ (0.05 ) $ 3.82 The impact of adopting the new revenue standard on the Company’s Unaudited Statement of Financial Condition through the date of September 30, 2018 is as follows (in thousands): September 30, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Financial Condition Accounts receivable $ 378,705 $ (62,968 ) $ 315,737 Income taxes payable $ 9,581 $ (5,414 ) $ 4,167 Other accrued liabilities $ 106,328 $ (2,166 ) $ 104,162 Deferred revenue $ 441,884 $ (34,851 ) $ 407,033 Retained earnings $ 1,755,727 $ (20,537 ) $ 1,735,190 The table that follows presents the disaggregated revenues for the periods indicated (in thousands): For the Three Months ended September 30, 2018 Segments Index Analytics All Other Total Product Types Recurring subscriptions $ 121,285 $ 118,857 $ 27,234 $ 267,376 Asset-based fees 82,007 — — 82,007 Non-recurring 6,902 1,041 608 8,551 Total $ 210,194 $ 119,898 $ 27,842 $ 357,934 For the Nine Months ended September 30, 2018 Segments Index Analytics All Other Total Product Types Recurring subscriptions $ 354,116 $ 354,629 $ 86,185 $ 794,930 Asset-based fees 255,126 — — 255,126 Non-recurring 15,800 3,375 3,065 22,240 Total $ 625,042 $ 358,004 $ 89,250 $ 1,072,296 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 services and products provided in advance of billing and therefore such contracts 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. September 30, 2018 Accounts receivable Deferred revenue Opening (1/1/2018) $ 473,400 $ 494,591 Closing (09/30/2018) 378,705 441,884 Increase/(decrease) $ (94,695 ) $ (52,707 ) The amount of revenue recognized in the period that was included in the opening current deferred revenue, which reflects the contract liability amounts, was $420.7 million. The difference between the opening and closing balances of the Company’s deferred revenue was primarily driven by an increase in the amortization of deferred revenue to operating revenues, partially offset by an increase in billings. MSCI had an insignificant long-term deferred revenue balance as of September 30, 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 $420.5 million, which is expected to be recognized as follows: • Approximately $237.9 million of the remaining performance obligations over the next 12-month period; • Approximately $123.0 million of the remaining performance obligations over the second 12-month period; • Approximately $45.0 million of the remaining performance obligations over the third 12-month period; and • Approximately $14.6 million of the remaining performance obligations in the periods thereafter.

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 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 Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands, except per share data) Net income $ 123,832 $ 85,153 $ 355,753 $ 239,370 Basic weighted average common shares outstanding 88,796 90,112 89,323 90,406 Effect of dilutive securities: Stock options and restricted stock units 2,576 1,756 2,520 1,325 Diluted weighted average common shares outstanding 91,372 91,868 91,843 91,731 Earnings per basic common share $ 1.39 $ 0.94 $ 3.98 $ 2.65 Earnings per diluted common share $ 1.36 $ 0.93 $ 3.87 $ 2.61

Property, Equipment and Leaseho

Property, Equipment and Leasehold Improvements	9 Months Ended
	Sep. 30, 2018
Property Plant And Equipment [Abstract]
Property, Equipment and Leasehold Improvements	5. PROPERTY, EQUIPMENT AND LEASEHOLD IMPROVEMENTS Property, equipment and leasehold improvements at September 30, 2018 and December 31, 2017 consisted of the following: As of September 30, December 31, 2018 2017 (in thousands) Computer & related equipment $ 196,322 $ 200,592 Furniture & fixtures 10,447 10,591 Leasehold improvements 50,866 51,128 Work-in-process 3,728 3,406 Subtotal 261,363 265,717 Accumulated depreciation and amortization (178,618 ) (171,280 ) Property, equipment and leasehold improvements, net (1) $ 82,745 $ 94,437 (1) Depreciation and amortization expense of property, equipment and leasehold improvements was $7.5 million and $9.3 million for the three months ended September 30, 2018 and 2017, respectively. Depreciation and amortization expense of property, equipment and leasehold improvements was $23.0 million and $27.3 million for the nine months ended September 30, 2018 and 2017, respectively.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 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 Changes to goodwill — (11,635 ) (2) — (11,635 ) Foreign exchange translation adjustment (1,228 ) — (756 ) (1,984 ) Goodwill at September 30, 2018 $ 1,204,172 $ 290,976 $ 51,854 $ 1,547,002 (1) (2) . The Company completed its annual goodwill impairment test as of July 1, 2018 on its four reporting units, which are the same as its four operating segments, and no impairments were noted. The Company performed a step zero, qualitative impairment test on its four operating segments and determined that it was more likely than not that the fair value for each was not less than the carrying value. Intangible Assets Amortization expense related to intangible assets for both the three months ended September 30, 2018 and 2017 was $11.7 million and $10.6 million, respectively. The amortization expense of acquired intangible assets for both the three months ended September 30, 2018 and 2017 was $9.0 million and $9.3 million, respectively. The amortization expense of internally developed capitalized software for both the three months ended September 30, 2018 and 2017 was $2.7 million and $1.3 million, respectively. Amortization expense related to intangible assets for both the nine months ended September 30, 2018 and 2017 was $42.6 million and $33.0 million, respectively. The amortization expense of acquired intangible assets for both the nine months ended September 30, 2018 and 2017 was $35.2 million and $29.9 million, respectively. The amortization expense of internally developed capitalized software for both the nine months ended September 30, 2018 and 2017 was $7.4 million and $3.1 million, respectively. During the nine months ended September 30, 2018, management decided to discontinue the use of the IPD tradename utilized by the Real Estate segment and has rebranded the segment to MSCI Real Estate. As a result, the remaining unamortized value of $7.9 million was written off. The gross carrying and accumulated amortization amounts related to the Company’s identifiable intangible assets were as follows: As of September 30, December 31, 2018 2017 (in thousands) Gross intangible assets: Customer relationships (1) $ 356,699 $ 361,199 Trademarks/trade names (1) 208,320 223,382 Technology/software (1), (2) 233,109 225,407 Proprietary data 28,627 28,627 Subtotal 826,755 838,615 Foreign exchange translation adjustment (8,550 ) (9,167 ) Total gross intangible assets $ 818,205 $ 829,448 Accumulated amortization: Customer relationships (1) $ (204,417 ) $ (189,100 ) Trademarks/trade names (1) (120,600 ) (116,691 ) Technology/software (1), (2) (195,978 ) (193,095 ) Proprietary data (11,753 ) (10,352 ) Subtotal (532,748 ) (509,238 ) Foreign exchange translation adjustment 1,988 1,626 Total accumulated amortization $ (530,760 ) $ (507,612 ) Net intangible assets: Customer relationships (1) $ 152,282 $ 172,099 Trademarks/trade names (1) 87,720 106,691 Technology/software (1), (2) 37,131 32,312 Proprietary data 16,874 18,275 Subtotal 294,007 329,377 Foreign exchange translation adjustment (6,562 ) (7,541 ) Total net intangible assets $ 287,445 $ 321,836 (1) (2) 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 $ 11,787 2019 46,467 2020 44,663 2021 40,443 2022 35,498 Thereafter 108,587 Total $ 287,445

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 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-cancellable 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 September 30, 2018 and 2017 was $6.0 million and $6.1 million, respectively. Rent expense for the nine months ended September 30, 2018 and 2017 was $18.8 million and $18.0 million, respectively. Senior Notes. The Company has issued an aggregate of $2.6 billion in senior unsecured notes (collectively, the “Senior Notes”) in the four discrete private offerings presented in the following table: Principal amount outstanding at Carrying value at Carrying value at Fair Value at Fair Value at Maturity Date September 30, 2018 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (in thousands) Long-term debt 5.25% senior unsecured notes due 2024 November 15, 2024 $ 800,000 $ 792,760 $ 791,880 $ 822,680 $ 847,064 5.75% senior unsecured notes due 2025 August 15, 2025 800,000 792,754 791,967 839,824 858,848 4.75% senior unsecured notes due 2026 August 1, 2026 500,000 494,749 494,246 497,290 525,185 5.375% senior unsecured notes due 2027 May 15, 2027 500,000 494,353 - 511,650 - Total debt $ 2,600,000 $ 2,574,616 $ 2,078,093 $ 2,671,444 $ 2,231,097 The fair market value of the Company’s debt obligations is determined in accordance with accounting standards related to the determination of fair value and represents Level 2 valuations, which are based on one or more quoted prices in markets that are not considered to be active or for which all significant inputs are observable, either directly or indirectly. The Company utilizes the market approach and obtains security pricing from a vendor who uses broker quotes and third-party pricing services to determine fair values. The $800.0 million aggregate principal amount of 5.25% senior unsecured notes due 2024 (the “2024 Senior Notes”) are scheduled to mature and be paid in full on November 15, 2024. At any time prior to November 15, 2019, the Company may redeem all or part of the 2024 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption. In addition, the Company may redeem all or part of the 2024 Senior Notes, together with accrued and unpaid interest, on or after November 15, 2019, at redemption prices set forth in the indenture governing the 2024 Senior Notes. The $800.0 million aggregate principal amount of 5.75% senior unsecured notes due 2025 (the “2025 Senior Notes”) are scheduled to mature and be paid in full on August 15, 2025. At any time prior to August 15, 2020, the Company may redeem all or part of the 2025 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption. In addition, the Company may redeem all or part of the 2025 Senior Notes, together with accrued and unpaid interest, on or after August 15, 2020, at redemption prices set forth in the indenture governing the 2025 Senior Notes. The $500.0 million aggregate principal amount of 4.75% senior unsecured notes due 2026 (the “2026 Senior Notes”) are scheduled to mature and be paid in full on August 1, 2026. At any time prior to August 1, 2021, the Company may redeem all or part of the 2026 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption. In addition, the Company may redeem all or part of the 2026 Senior Notes, together with accrued and unpaid interest, on or after August 1, 2021, at redemption prices set forth in the indenture governing the 2026 Senior Notes. 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 plus accrued and unpaid interest, if any, to the redemption date. On May 18, 2018, the Company completed its private offering of $500.0 million aggregate principal amount of 5.375% senior unsecured notes due 2027 (the “2027 Senior Notes”) reflected in the table above. The $495.0 million of net proceeds from the offering of the 2027 Senior Notes were allocated for general corporate purposes, including, without limitation, buybacks of the Company’s common stock and potential acquisitions. The 2027 Senior Notes are scheduled to mature and be paid in full on May 15, 2027. Interest payments attributable to the 2024 Senior Notes and 2027 Senior Notes are due on May 15th and November 15th of each year. Interest payments attributable to the 2025 Senior Notes are due on February 15th and August 15th of each year. Interest payments attributable to the 2026 Senior Notes are due on February 1st and August 1st of each year. The first interest payment attributable to the 2027 Senior Notes will be made on November 15, 2018. Revolver. On November 20, 2014, the Company entered into a $200.0 million senior unsecured revolving credit agreement (as amended, the “Revolving Credit Agreement”) with a syndicate of banks. The Revolving Credit Agreement had an initial term of five years with an option to extend for two additional one-year terms. On August 4, 2016, the Company entered into Amendment No. 1 (the “First Amendment”) to the Revolving Credit Agreement. The First Amendment, among other things, (i) increased aggregate commitments available to be borrowed to $220.0 million, (ii) increased the maximum consolidated leverage ratio and (iii) extended the initial term to August 2021 with an option to extend for an additional one-year term. On May 15, 2018, the Company entered into Amendment No. 2 (the “Second Amendment”) to the Revolving Credit Agreement. The Second Amendment, among other things, (i) increased aggregate commitments available to be borrowed to $250.0 million, (ii) extended the term to May 2023 with an option to extend for an additional one-year term and (iii) decreased the applicable rate and applicable fee rate for loans and commitments. At September 30, 2018, the Revolving Credit Agreement was undrawn. In connection with the closings of the Senior Notes offerings and entry into the Revolving Credit Agreement and the First and Second Amendments, the Company paid certain fees which, together with the existing fees related to prior credit facilities, are being amortized over their related lives. At September 30, 2018, $27.3 million of the deferred financing fees remain unamortized, $0.4 million of which is included in “Prepaid and other assets,” $1.5 million of which is included in “Other non-current assets” and $25.4 million of which is grouped and presented as part of “Long-term debt” on the Unaudited Condensed Consolidated Statement of Financial Condition.

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Shareholders' Equity	8. SHAREHOLDERS’ EQUITY Return of capital . On October 26, 2016, the Board of Directors approved a stock repurchase program for the purchase of up to $750.0 million worth of shares of the Company’s common stock (together with the amount then remaining under a previously existing share repurchase program, the “2016 Repurchase Program”). On May 1, 2018, the Board of Directors authorized an additional stock repurchase program for the purchase of up to $1.0 billion worth of shares of the Company’s common stock (together with the $523.1 million of authorization then remaining under the 2016 Repurchase Program, the “2018 Repurchase Program”). Share repurchases made pursuant to the 2018 Repurchase Program may take place in the open market or in privately negotiated transactions from time to time based on market and other conditions. This authorization may be modified, suspended or terminated by the Board of Directors at any time without prior notice. As of September 30, 2018, there was $1,464.2 million of available authorization remaining under the 2018 Repurchase Program. The following table provides information with respect to repurchases of the Company’s common stock made on the open market: Nine Months Ended Average Price Paid Per Share Total Number of Shares Repurchased Dollar Value of Shares Repurchased (in thousands) September 30, 2018 $ 149.82 1,794 $ 268,850 September 30, 2017 $ 87.95 1,556 $ 136,850 The following table presents dividends declared per common share as well as total amounts declared, distributed and deferred for the periods indicated: Dividends (in thousands, except per share amounts) Per Share Declared Distributed Deferred 2018 Three Months Ended March 31, $ 0.38 $ 34,848 $ 34,900 $ (52 ) Three Months Ended June 30, 0.38 34,254 33,935 319 Three Months Ended September 30, 0.58 52,264 51,764 500 Total $ 1.34 $ 121,366 $ 120,599 $ 767 2017 Three Months Ended March 31, $ 0.28 $ 25,769 $ 25,500 $ 269 Three Months Ended June 30, 0.28 25,710 25,444 266 Three Months Ended September 30, 0.38 34,768 34,403 365 Total $ 0.94 $ 86,247 $ 85,347 $ 900 Common Stock. The following table presents activity related to shares of common stock issued and repurchased during the nine months ended September 30, 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 Dividend payable/paid 117 (117 ) — Common stock issued and exercise of stock options 18,944 — 18,944 Shares withheld for tax withholding and exercises — (3,178 ) (3,178 ) Shares repurchased under stock repurchase programs — (1,042,966 ) (1,042,966 ) Shares issued to directors 6,059 (5,618 ) 441 Balance At June 30, 2018 129,978,881 (41,145,982 ) 88,832,899 Dividend payable/paid 165 (165 ) — Common stock issued and exercise of stock options 23,492 — 23,492 Shares withheld for tax withholding and exercises — (3,705 ) (3,705 ) Shares repurchased under stock repurchase programs — (259,357 ) (259,357 ) Shares issued to directors — — — Balance At September 30, 2018 130,002,538 (41,409,209 ) 88,593,329

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	9. INCOME TAXES The Company’s provision for income taxes was $86.9 million and $100.6 million for the nine months ended September 30, 2018 and 2017, respectively. These amounts reflect effective tax rates of 19.6% and 29.6% for the nine months ended September 30, 2018 and 2017, respectively. The decrease in the provision for income taxes was primarily driven by a decline in the operating tax rate and the impact of discrete items as discussed below, partially offset by higher income before provision for income taxes. The effective tax rate of 19.6% for the nine months ended September 30, 2018 reflects the Company’s estimate of the effective tax rate for the period and was impacted by certain discrete items totaling $19.0 million that decreased the Company’s effective tax rate by 3.4 percentage points. For the nine months ended September 30, 2018, these discrete items include $8.8 million of excess tax benefits related to stock-based compensation and $11.8 million related to the release of valuation allowances previously recorded on capital loss carryforwards. The Company recognized $7.8 million of the release of the valuation allowance in the three months ended September 30, 2018 due to the execution of the agreement to sell InvestorForce in July 2018 and $4.0 million of the release of the valuation allowance in April 2018 related to the FEA divestiture. See Note 11, “Divestitures,” for additional information. The discrete items also include a $1.6 million net adjustment benefit relating to the adjustment resulting from the Company’s provisional accounting for the effects of Tax Reform. 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 nine months ended September 30, 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 September 30, 2018, including the charges recognized in the year ended December 31, 2017 and in the nine months ended September 30, 2018, totaled $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 2006 through 2017. As a result of having previously been a member of the Morgan Stanley consolidated group, the Company may have future settlements with Morgan Stanley related to the ultimate disposition of their New York State and New York City examination relating to the tax years 2007 and 2008 and their IRS examination relating to the tax years 2006 through 2008. The Company does not believe it has any material exposure to the New York State and New York City income tax examinations. Additionally, the Company believes it has adequate reserves for any tax issues that may arise out of the IRS examination relating to the tax years 2006 through 2008 and therefore does not believe any related settlement with Morgan Stanley will have a material impact. The Company regularly assesses the likelihood of additional assessments in each of the taxing jurisdictions in which it files income tax returns. The Company has established unrecognized tax benefits that the Company believes are adequate in relation to the potential for additional assessments. Once established, the Company adjusts unrecognized tax benefits only when more information is available or when an event occurs necessitating a change. As part of the Company’s periodic review of unrecognized tax benefits and based on new information regarding the status of federal and state examinations, the Company’s unrecognized tax benefits were remeasured. 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	9 Months Ended
	Sep. 30, 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 its 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 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 Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands) Operating revenues Index $ 210,194 $ 184,594 $ 625,042 $ 525,185 Analytics 119,898 114,972 358,004 340,759 All Other 27,842 22,531 89,250 73,449 Total $ 357,934 $ 322,097 $ 1,072,296 $ 939,393 The following table presents segment profitability and a reconciliation to net income for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands) Index Adjusted EBITDA $ 154,477 $ 134,342 $ 457,923 $ 379,538 Analytics Adjusted EBITDA 37,046 33,078 106,966 94,483 All Other Adjusted EBITDA 4,014 1,318 17,782 11,919 Total operating segment profitability 195,537 168,738 582,671 485,940 Amortization of intangible assets 11,681 10,614 42,556 32,987 Depreciation and amortization of property, equipment and leasehold improvements 7,453 9,325 23,035 27,322 Operating income 176,403 148,799 517,080 425,631 Other expense (income), net 29,557 27,996 74,473 85,692 Provision for income taxes 23,014 35,650 86,854 100,569 Net income $ 123,832 $ 85,153 $ 355,753 $ 239,370 Revenue by geography is based on the shipping address of the ultimate customer utilizing the product. The following table presents revenue by geographic area for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands) Revenues Americas: United States $ 167,415 $ 159,123 $ 498,270 $ 459,958 Other 15,118 11,997 43,529 34,949 Total Americas 182,533 171,120 541,799 494,907 Europe, the Middle East and Africa ("EMEA"): United Kingdom 52,997 48,878 159,699 143,140 Other 69,602 61,567 218,999 185,655 Total EMEA 122,599 110,445 378,698 328,795 Asia & Australia: Japan 16,572 13,577 48,941 39,640 Other 36,230 26,955 102,858 76,051 Total Asia & Australia 52,802 40,532 151,799 115,691 Total $ 357,934 $ 322,097 $ 1,072,296 $ 939,393 Long-lived assets consist of property, equipment, leasehold improvements, goodwill and intangible assets, net of accumulated depreciation and amortization. The following table presents long-lived assets by geographic area on the dates indicated: As of September 30, December 31, 2018 2017 (in thousands) Long-lived assets Americas: United States $ 1,805,085 $ 1,847,605 Other 3,507 1,685 Total Americas 1,808,592 1,849,290 EMEA: United Kingdom 82,004 94,782 Other 18,750 22,394 Total EMEA 100,754 117,176 Asia & Australia: Japan 318 432 Other 7,528 9,996 Total Asia & Australia 7,846 10,428 Total $ 1,917,192 $ 1,976,894

Divestitures

Divestitures	9 Months Ended
	Sep. 30, 2018
Discontinued Operations And Disposal Groups [Abstract]
Divestitures	11. DIVESTITURES On April 9, 2018, MSCI completed the FEA divestiture for $21.0 million in cash. The sale included $2.9 million of goodwill, $2.7 million of fully amortized identifiable intangible assets, $6.1 million of other net assets and $1.4 million of cash costs, which resulted in a gain of $10.6 million upon the divestiture. FEA was included as a component of the Analytics segment through the date of divestiture. The results of operations from FEA were not material to the Company. On July 25, 2018, MSCI entered into a definitive agreement to sell InvestorForce for $62.0 million, subject to working capital adjustments and, as a result, the assets and liabilities associated with InvestorForce are reported as “Assets held-for-sale” and “Liabilities held-for-sale,” respectively, in the Unaudited Condensed Consolidated Statement of Financial Condition as of September 30, 2018. On October 12, 2018, the Company completed the InvestorForce divestiture and received $62.8 million in cash and currently estimates that it will realize a pre-tax gain of approximately $47.0 million, each of which may be subject to a final working capital adjustment, and an after-tax gain currently estimated to be approximately $41.0 million as a result of the transaction. The carrying amounts of the major classes of assets and liabilities of InvestorForce as of September 30, 2018 were as follows: As of September 30, 2018 (in thousands) ASSETS Accounts receivable $ 4,427 Prepaid and other assets 182 Total current assets 4,609 Property, equipment and leasehold improvements (net of accumulated depreciation and amortization of $543) 47 Goodwill 8,691 Intangible assets (net of accumulated amortization of $5,068) 4,032 Other non-current assets 24 Deferred tax assets 1,592 Total non-current assets 14,386 Assets held-for-sale $ 18,995 LIABILITIES Accrued compensation and related benefits $ 810 Other accrued liabilities 108 Deferred revenue 4,316 Total current liabilities 5,234 Liabilities held-for-sale $ 5,234

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	12. SUBSEQUENT EVENTS On October 30, 2018, the Board of Directors declared a cash dividend of $0.58 per share for fourth quarter 2018. The fourth quarter 2018 dividend is payable on November 30, 2018 to shareholders of record as of the close of trading on November 16, 2018. Subsequent to the three months ended September 30, 2018 and through October 31, 2018, the Company repurchased an additional 0.8 million shares of common stock at an average price of $153.92 per share for a total value of $119.6 million.

Introduction and Basis of Pre_2

Introduction and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 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, except assets and liabilities held-for-sale associated with Investor Force Holdings, Inc. (“InvestorForce”), necessary to state fairly the financial condition as of September 30, 2018 and December 31, 2017, the results of operations and comprehensive income for the three and nine months ended September 30, 2018 and 2017 and cash flows for the nine months ended September 30, 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 nine months ended September 30, 2018 and 2017, BlackRock, Inc. accounted for 12.2% and 11.1% of the Company’s consolidated operating revenues, respectively. For the nine months ended September 30, 2018 and 2017, BlackRock, Inc. accounted for 20.7% and 19.6% 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 nine months ended September 30, 2018 and 2017.
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 July 2018, the FASB issued Accounting Standards Update No. 2018-10, “ Codification Improvements to Topic 842, Leases, Targeted Improvements, The Company has reached a decision as to what system it will use to manage the accounting for leases, determined the contracts that would be considered leases under the new guidance and is currently in the process of implementing the system and establishing the appropriate controls and procedures. The Company will adopt the new lease standard as of January 1, 2019 using the optional transition method provided under ASU 2018-11 and is continuing to evaluate the potential impact that ASU 2016-02, ASU 2018-10 and ASU 2018-11 will have on its condensed consolidated financial statements. 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 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, In June 2018, the FASB issued Accounting Standards Update No. 2018-07, “ Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, In August 2018, the FASB issued Accounting Standards Update No. 2018-15, “ Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40) In August 2018, the SEC issued release number 33-10532, “ Disclosure Update and Simplification,

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2018
Disaggregation of Revenue	The table that follows presents the disaggregated revenues for the periods indicated (in thousands): For the Three Months ended September 30, 2018 Segments Index Analytics All Other Total Product Types Recurring subscriptions $ 121,285 $ 118,857 $ 27,234 $ 267,376 Asset-based fees 82,007 — — 82,007 Non-recurring 6,902 1,041 608 8,551 Total $ 210,194 $ 119,898 $ 27,842 $ 357,934 For the Nine Months ended September 30, 2018 Segments Index Analytics All Other Total Product Types Recurring subscriptions $ 354,116 $ 354,629 $ 86,185 $ 794,930 Asset-based fees 255,126 — — 255,126 Non-recurring 15,800 3,375 3,065 22,240 Total $ 625,042 $ 358,004 $ 89,250 $ 1,072,296
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 September 30, 2018 is as follows (in thousands): For the Three Months ended September 30, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Income Operating revenues $ 357,934 $ (1,052 ) $ 356,882 Operating income $ 176,403 $ (1,052 ) $ 175,351 Income before provision for income taxes $ 146,846 $ (1,052 ) $ 145,794 Provision for income taxes $ 23,014 $ (210 ) $ 22,804 Net income $ 123,832 $ (842 ) $ 122,990 Earnings per basic common share $ 1.39 $ (0.01 ) $ 1.38 Earnings per diluted common share $ 1.36 $ (0.01 ) $ 1.35 For the Nine Months ended September 30, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Income Operating revenues $ 1,072,296 $ (5,502 ) $ 1,066,794 Operating income $ 517,080 $ (5,502 ) $ 511,578 Income before provision for income taxes $ 442,607 $ (5,502 ) $ 437,105 Provision for income taxes $ 86,854 $ (1,100 ) $ 85,754 Net income $ 355,753 $ (4,402 ) $ 351,351 Earnings per basic common share $ 3.98 $ (0.05 ) $ 3.93 Earnings per diluted common share $ 3.87 $ (0.05 ) $ 3.82 The impact of adopting the new revenue standard on the Company’s Unaudited Statement of Financial Condition through the date of September 30, 2018 is as follows (in thousands): September 30, 2018 Selected line items As reported Impact of Change Without Adoption of ASC 606 Statement of Financial Condition Accounts receivable $ 378,705 $ (62,968 ) $ 315,737 Income taxes payable $ 9,581 $ (5,414 ) $ 4,167 Other accrued liabilities $ 106,328 $ (2,166 ) $ 104,162 Deferred revenue $ 441,884 $ (34,851 ) $ 407,033 Retained earnings $ 1,755,727 $ (20,537 ) $ 1,735,190
Schedule of Accounts Receivable and Deferred Revenue	September 30, 2018 Accounts receivable Deferred revenue Opening (1/1/2018) $ 473,400 $ 494,591 Closing (09/30/2018) 378,705 441,884 Increase/(decrease) $ (94,695 ) $ (52,707 )

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 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 Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands, except per share data) Net income $ 123,832 $ 85,153 $ 355,753 $ 239,370 Basic weighted average common shares outstanding 88,796 90,112 89,323 90,406 Effect of dilutive securities: Stock options and restricted stock units 2,576 1,756 2,520 1,325 Diluted weighted average common shares outstanding 91,372 91,868 91,843 91,731 Earnings per basic common share $ 1.39 $ 0.94 $ 3.98 $ 2.65 Earnings per diluted common share $ 1.36 $ 0.93 $ 3.87 $ 2.61

Property, Equipment and Lease_2

Property, Equipment and Leasehold Improvements (Tables)	9 Months Ended
	Sep. 30, 2018
Property Plant And Equipment [Abstract]
Schedule of Property, Equipment and Leasehold Improvements	Property, equipment and leasehold improvements at September 30, 2018 and December 31, 2017 consisted of the following: As of September 30, December 31, 2018 2017 (in thousands) Computer & related equipment $ 196,322 $ 200,592 Furniture & fixtures 10,447 10,591 Leasehold improvements 50,866 51,128 Work-in-process 3,728 3,406 Subtotal 261,363 265,717 Accumulated depreciation and amortization (178,618 ) (171,280 ) Property, equipment and leasehold improvements, net (1) $ 82,745 $ 94,437 (1)

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 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 Changes to goodwill — (11,635 ) (2) — (11,635 ) Foreign exchange translation adjustment (1,228 ) — (756 ) (1,984 ) Goodwill at September 30, 2018 $ 1,204,172 $ 290,976 $ 51,854 $ 1,547,002 (1) (2) .
Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Identifiable Intangible Assets	The gross carrying and accumulated amortization amounts related to the Company’s identifiable intangible assets were as follows: As of September 30, December 31, 2018 2017 (in thousands) Gross intangible assets: Customer relationships (1) $ 356,699 $ 361,199 Trademarks/trade names (1) 208,320 223,382 Technology/software (1), (2) 233,109 225,407 Proprietary data 28,627 28,627 Subtotal 826,755 838,615 Foreign exchange translation adjustment (8,550 ) (9,167 ) Total gross intangible assets $ 818,205 $ 829,448 Accumulated amortization: Customer relationships (1) $ (204,417 ) $ (189,100 ) Trademarks/trade names (1) (120,600 ) (116,691 ) Technology/software (1), (2) (195,978 ) (193,095 ) Proprietary data (11,753 ) (10,352 ) Subtotal (532,748 ) (509,238 ) Foreign exchange translation adjustment 1,988 1,626 Total accumulated amortization $ (530,760 ) $ (507,612 ) Net intangible assets: Customer relationships (1) $ 152,282 $ 172,099 Trademarks/trade names (1) 87,720 106,691 Technology/software (1), (2) 37,131 32,312 Proprietary data 16,874 18,275 Subtotal 294,007 329,377 Foreign exchange translation adjustment (6,562 ) (7,541 ) Total net intangible assets $ 287,445 $ 321,836 (1) (2)
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 $ 11,787 2019 46,467 2020 44,663 2021 40,443 2022 35,498 Thereafter 108,587 Total $ 287,445

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
Schedule of Senior Unsecured Notes	The Company has issued an aggregate of $2.6 billion in senior unsecured notes (collectively, the “Senior Notes”) in the four discrete private offerings presented in the following table: Principal amount outstanding at Carrying value at Carrying value at Fair Value at Fair Value at Maturity Date September 30, 2018 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (in thousands) Long-term debt 5.25% senior unsecured notes due 2024 November 15, 2024 $ 800,000 $ 792,760 $ 791,880 $ 822,680 $ 847,064 5.75% senior unsecured notes due 2025 August 15, 2025 800,000 792,754 791,967 839,824 858,848 4.75% senior unsecured notes due 2026 August 1, 2026 500,000 494,749 494,246 497,290 525,185 5.375% senior unsecured notes due 2027 May 15, 2027 500,000 494,353 - 511,650 - Total debt $ 2,600,000 $ 2,574,616 $ 2,078,093 $ 2,671,444 $ 2,231,097

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	9 Months Ended
	Sep. 30, 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: Nine Months Ended Average Price Paid Per Share Total Number of Shares Repurchased Dollar Value of Shares Repurchased (in thousands) September 30, 2018 $ 149.82 1,794 $ 268,850 September 30, 2017 $ 87.95 1,556 $ 136,850
Schedule of Dividends Declared Per Common Share and Total Amounts Declared, Distributed and Deferred	The following table presents dividends declared per common share as well as total amounts declared, distributed and deferred for the periods indicated: Dividends (in thousands, except per share amounts) Per Share Declared Distributed Deferred 2018 Three Months Ended March 31, $ 0.38 $ 34,848 $ 34,900 $ (52 ) Three Months Ended June 30, 0.38 34,254 33,935 319 Three Months Ended September 30, 0.58 52,264 51,764 500 Total $ 1.34 $ 121,366 $ 120,599 $ 767 2017 Three Months Ended March 31, $ 0.28 $ 25,769 $ 25,500 $ 269 Three Months Ended June 30, 0.28 25,710 25,444 266 Three Months Ended September 30, 0.38 34,768 34,403 365 Total $ 0.94 $ 86,247 $ 85,347 $ 900
Summary of Activity Related to Shares of Common Stock Issued and Repurchased	The following table presents activity related to shares of common stock issued and repurchased during the nine months ended September 30, 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 Dividend payable/paid 117 (117 ) — Common stock issued and exercise of stock options 18,944 — 18,944 Shares withheld for tax withholding and exercises — (3,178 ) (3,178 ) Shares repurchased under stock repurchase programs — (1,042,966 ) (1,042,966 ) Shares issued to directors 6,059 (5,618 ) 441 Balance At June 30, 2018 129,978,881 (41,145,982 ) 88,832,899 Dividend payable/paid 165 (165 ) — Common stock issued and exercise of stock options 23,492 — 23,492 Shares withheld for tax withholding and exercises — (3,705 ) (3,705 ) Shares repurchased under stock repurchase programs — (259,357 ) (259,357 ) Shares issued to directors — — — Balance At September 30, 2018 130,002,538 (41,409,209 ) 88,593,329

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 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 Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands) Operating revenues Index $ 210,194 $ 184,594 $ 625,042 $ 525,185 Analytics 119,898 114,972 358,004 340,759 All Other 27,842 22,531 89,250 73,449 Total $ 357,934 $ 322,097 $ 1,072,296 $ 939,393
Segment Profitability and Reconciliation to Net Income	The following table presents segment profitability and a reconciliation to net income for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands) Index Adjusted EBITDA $ 154,477 $ 134,342 $ 457,923 $ 379,538 Analytics Adjusted EBITDA 37,046 33,078 106,966 94,483 All Other Adjusted EBITDA 4,014 1,318 17,782 11,919 Total operating segment profitability 195,537 168,738 582,671 485,940 Amortization of intangible assets 11,681 10,614 42,556 32,987 Depreciation and amortization of property, equipment and leasehold improvements 7,453 9,325 23,035 27,322 Operating income 176,403 148,799 517,080 425,631 Other expense (income), net 29,557 27,996 74,473 85,692 Provision for income taxes 23,014 35,650 86,854 100,569 Net income $ 123,832 $ 85,153 $ 355,753 $ 239,370
Revenue by Geographic Area	Revenue by geography is based on the shipping address of the ultimate customer utilizing the product. The following table presents revenue by geographic area for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 (in thousands) Revenues Americas: United States $ 167,415 $ 159,123 $ 498,270 $ 459,958 Other 15,118 11,997 43,529 34,949 Total Americas 182,533 171,120 541,799 494,907 Europe, the Middle East and Africa ("EMEA"): United Kingdom 52,997 48,878 159,699 143,140 Other 69,602 61,567 218,999 185,655 Total EMEA 122,599 110,445 378,698 328,795 Asia & Australia: Japan 16,572 13,577 48,941 39,640 Other 36,230 26,955 102,858 76,051 Total Asia & Australia 52,802 40,532 151,799 115,691 Total $ 357,934 $ 322,097 $ 1,072,296 $ 939,393
Long-Lived Assets by Geographic Area	Long-lived assets consist of property, equipment, leasehold improvements, goodwill and intangible assets, net of accumulated depreciation and amortization. The following table presents long-lived assets by geographic area on the dates indicated: As of September 30, December 31, 2018 2017 (in thousands) Long-lived assets Americas: United States $ 1,805,085 $ 1,847,605 Other 3,507 1,685 Total Americas 1,808,592 1,849,290 EMEA: United Kingdom 82,004 94,782 Other 18,750 22,394 Total EMEA 100,754 117,176 Asia & Australia: Japan 318 432 Other 7,528 9,996 Total Asia & Australia 7,846 10,428 Total $ 1,917,192 $ 1,976,894

Divestitures (Tables)

Divestitures (Tables)	9 Months Ended
	Sep. 30, 2018
Investor Force [Member]
Carrying Amounts of Major Classes of Assets and Liabilities	The carrying amounts of the major classes of assets and liabilities of InvestorForce as of September 30, 2018 were as follows: As of September 30, 2018 (in thousands) ASSETS Accounts receivable $ 4,427 Prepaid and other assets 182 Total current assets 4,609 Property, equipment and leasehold improvements (net of accumulated depreciation and amortization of $543) 47 Goodwill 8,691 Intangible assets (net of accumulated amortization of $5,068) 4,032 Other non-current assets 24 Deferred tax assets 1,592 Total non-current assets 14,386 Assets held-for-sale $ 18,995 LIABILITIES Accrued compensation and related benefits $ 810 Other accrued liabilities 108 Deferred revenue 4,316 Total current liabilities 5,234 Liabilities held-for-sale $ 5,234

Introduction and Basis of Pre_3

Introduction and Basis of Presentation - Additional Information (Detail) - Operating Revenues [Member] - Customer Concentration Risk [Member] - Customer	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
BlackRock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	12.20%	11.10%
Index [Member] | BlackRock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer	20.70%	19.60%
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 U_2

Recent Accounting Standards Updates - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017
New Accounting Pronouncements And Changes In Accounting Principles [Abstract]
Non-service related pension costs	$ 0.1	$ 0.4

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Detail) $ in Millions	9 Months Ended
	Sep. 30, 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 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.
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	$ 420.7
Remaining performance obligations	420.5
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	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Accounts receivable	$ 378,705		$ 327,597
Income taxes payable	9,581		14,828
Other accrued liabilities	106,328		85,710
Deferred revenue	441,884		374,365
Retained earnings	1,755,727		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	(62,968)		145,803
Income taxes payable	(5,414)		4,314
Other accrued liabilities	(2,166)		5,128
Deferred revenue	(34,851)		120,226
Retained earnings	$ (20,537)		$ 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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Income
Operating revenues	$ 357,934	$ 322,097	$ 1,072,296	$ 939,393
Operating income	176,403	148,799	517,080	425,631
Income before provision for income taxes	146,846	120,803	442,607	339,939
Provision for income taxes	23,014	35,650	86,854	100,569
Net income	$ 123,832	$ 85,153	$ 355,753	$ 239,370
Earnings per basic common share	$ 1.39	$ 0.94	$ 3.98	$ 2.65
Earnings per diluted common share	$ 1.36	$ 0.93	$ 3.87	$ 2.61
Accounting Standards Update 2014-09 [Member] | Impact of Change [Member]
Statement of Income
Operating revenues	$ (1,052)		$ (5,502)
Operating income	(1,052)		(5,502)
Income before provision for income taxes	(1,052)		(5,502)
Provision for income taxes	(210)		(1,100)
Net income	$ (842)		$ (4,402)
Earnings per basic common share	$ (0.01)		$ (0.05)
Earnings per diluted common share	$ (0.01)		$ (0.05)
Accounting Standards Update 2014-09 [Member] | Without Adoption of ASC 606 [Member]
Statement of Income
Operating revenues	$ 356,882		$ 1,066,794
Operating income	175,351		511,578
Income before provision for income taxes	145,794		437,105
Provision for income taxes	22,804		85,754
Net income	$ 122,990		$ 351,351
Earnings per basic common share	$ 1.38		$ 3.93
Earnings per diluted common share	$ 1.35		$ 3.82

Revenue Recognition - Schedul_2

Revenue Recognition - Schedule of Impact of Adopting New Revenue Standard on Company's Unaudited Statement of Financial Condition (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Statement of Financial Condition
Accounts receivable	$ 378,705		$ 327,597
Income taxes payable	9,581		14,828
Other accrued liabilities	106,328		85,710
Deferred revenue	441,884		374,365
Retained earnings	1,755,727		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	(62,968)		145,803
Income taxes payable	(5,414)		4,314
Other accrued liabilities	(2,166)		5,128
Deferred revenue	(34,851)		120,226
Retained earnings	(20,537)		$ 16,135
Accounting Standards Update 2014-09 [Member] | Without Adoption of ASC 606 [Member]
Statement of Financial Condition
Accounts receivable	315,737
Income taxes payable	4,167
Other accrued liabilities	104,162
Deferred revenue	407,033
Retained earnings	$ 1,735,190

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 357,934	$ 1,072,296
Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	210,194	625,042
Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	119,898	358,004
All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	27,842	89,250
Recurring Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	267,376	794,930
Recurring Subscriptions [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	121,285	354,116
Recurring Subscriptions [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	118,857	354,629
Recurring Subscriptions [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	27,234	86,185
Asset-based Fees [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	82,007	255,126
Asset-based Fees [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	82,007	255,126
Non-recurring [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	8,551	22,240
Non-recurring [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	6,902	15,800
Non-recurring [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	1,041	3,375
Non-recurring [Member] | All Other [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 608	$ 3,065

Revenue Recognition - Schedul_3

Revenue Recognition - Schedule of Accounts Receivable and Deferred Revenue (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Revenue Recognition [Line Items]
Accounts receivable	$ 378,705			$ 327,597
Accounts receivable, Increase/(decrease)	60,250	$ 87,168
Deferred revenue	441,884			374,365
Deferred revenue	89,730	$ 38,932
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	(62,968)			145,803
Accounts receivable, Increase/(decrease)	(94,695)
Deferred revenue	(34,851)			$ 120,226
Deferred revenue	$ (52,707)

Revenue Recognition - Additio_2

Revenue Recognition - Additional Information (Detail 1) $ in Millions	Sep. 30, 2018USD ($)
Revenue Recognition [Line Items]
Remaining performance obligations	$ 420.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2018-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 237.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2019-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 123
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 45
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue Recognition [Line Items]
Remaining performance obligations	$ 14.6
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period

Earnings Per Common Share - Com

Earnings Per Common Share - Computation of Basic and Diluted EPS (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net income	$ 123,832	$ 85,153	$ 355,753	$ 239,370
Basic weighted average common shares outstanding	88,796	90,112	89,323	90,406
Effect of dilutive securities:
Stock options and restricted stock units	2,576	1,756	2,520	1,325
Diluted weighted average common shares outstanding	91,372	91,868	91,843	91,731
Earnings per basic common share	$ 1.39	$ 0.94	$ 3.98	$ 2.65
Earnings per diluted common share	$ 1.36	$ 0.93	$ 3.87	$ 2.61

Property, Equipment and Lease_3

Property, Equipment and Leasehold Improvements - Schedule of Property, Equipment and Leasehold Improvements (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property Plant And Equipment [Abstract]
Computer & related equipment	$ 196,322	$ 200,592
Furniture & fixtures	10,447	10,591
Leasehold improvements	50,866	51,128
Work-in-process	3,728	3,406
Subtotal	261,363	265,717
Accumulated depreciation and amortization	(178,618)	(171,280)
Property, equipment and leasehold improvements, net	$ 82,745	$ 94,437

Property, Equipment and Lease_4

Property, Equipment and Leasehold Improvements - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Property Plant And Equipment [Abstract]
Depreciation and amortization of property, equipment and leasehold improvements	$ 7,453	$ 9,325	$ 23,035	$ 27,322

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Schedule of Goodwill by Reportable Segment (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Goodwill [Line Items]
Goodwill, Beginning balance	$ 1,560,621
Changes to goodwill	(11,635)
Foreign exchange translation adjustment	(1,984)
Goodwill, Ending balance	1,547,002
Index [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	1,205,400
Foreign exchange translation adjustment	(1,228)
Goodwill, Ending balance	1,204,172
Analytics [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	302,611
Changes to goodwill	(11,635)
Goodwill, Ending balance	290,976
All Other [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	52,610
Foreign exchange translation adjustment	(756)
Goodwill, Ending balance	$ 51,854

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Goodwill by Reportable Segment (Parenthetical) (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 1,547,002	$ 1,560,621
All Other [Member]
Goodwill [Line Items]
Goodwill	51,854	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	20,300	21,000
Analytics [Member]
Goodwill [Line Items]
Goodwill	290,976	$ 302,611
Analytics [Member] | Financial Engineering Associates Inc [Member]
Goodwill [Line Items]
Impact of divestiture on goodwill	2,900
Analytics [Member] | Investor Force [Member]
Goodwill [Line Items]
Impact of divestiture on goodwill	$ 8,700

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)Segment	Sep. 30, 2017USD ($)
Goodwill [Line Items]
Number of reporting units | Segment			4
Number of operating segments | Segment			4
Impairment of goodwill			$ 0
Amortization of intangible assets	$ 11,681,000	$ 10,614,000	42,556,000	$ 32,987,000
Remaining unamortized value written off			7,900,000
Acquired Intangible Assets [Member]
Goodwill [Line Items]
Amortization of intangible assets	9,000,000	9,300,000	35,200,000	29,900,000
Capitalized Software [Member]
Goodwill [Line Items]
Amortization of intangible assets	$ 2,700,000	$ 1,300,000	$ 7,400,000	$ 3,100,000

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Identifiable Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	$ 818,205	$ 829,448
Accumulated amortization	(530,760)	(507,612)
Net carrying value	287,445	321,836
Customer Relationships [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	356,699	361,199
Accumulated amortization	(204,417)	(189,100)
Net carrying value	152,282	172,099
Trademarks/Trade Names [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	208,320	223,382
Accumulated amortization	(120,600)	(116,691)
Net carrying value	87,720	106,691
Technology/Software [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	233,109	225,407
Accumulated amortization	(195,978)	(193,095)
Net carrying value	37,131	32,312
Proprietary Data [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	28,627	28,627
Accumulated amortization	(11,753)	(10,352)
Net carrying value	16,874	18,275
Subtotal [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	826,755	838,615
Accumulated amortization	(532,748)	(509,238)
Net carrying value	294,007	329,377
Foreign Exchange Translation Adjustment [Member]
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying value	(8,550)	(9,167)
Accumulated amortization	1,988	1,626
Net carrying value	$ (6,562)	$ (7,541)

Goodwill and Intangible Asset_6

Goodwill and Intangible Assets - Estimated Amortization Expense for Remainder of 2018 and Succeeding Years (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Remainder 2,018	$ 11,787
2,019	46,467
2,020	44,663
2,021	40,443
2,022	35,498
Thereafter	108,587
Net carrying value	$ 287,445	$ 321,836

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	May 18, 2018	May 15, 2018	Aug. 04, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Nov. 20, 2014
Schedule Of Commitments And Contingencies [Line Items]
Annual rent expense				$ 6,000,000	$ 6,100,000	$ 18,800,000	$ 18,000,000
Debt instrument principal amount				2,600,000,000		2,600,000,000
Prepaid and Other Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				400,000		400,000
Other Non-Current Assets [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				1,500,000		1,500,000
Long-term Debt [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				25,400,000		$ 25,400,000
Revolving Credit Agreement [Member]
Schedule Of Commitments And Contingencies [Line Items]
Revolving credit facility, maximum borrowing		$ 250,000,000	$ 220,000,000					$ 200,000,000
Revolving credit agreement, term						5 years
Revolving credit agreement, extended term		1 year	1 year
5.250% Senior Unsecured Notes Due 2024 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 800,000,000		$ 800,000,000
Debt instrument interest rate				5.25%		5.25%
Maturity date						Nov. 15, 2024
Redemption description						At any time prior to November 15, 2019, the Company may redeem all or part of the 2024 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
5.75% Senior Unsecured Notes Due 2025 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 800,000,000		$ 800,000,000
Debt instrument interest rate				5.75%		5.75%
Maturity date						Aug. 15, 2025
Redemption description						At any time prior to August 15, 2020, the Company may redeem all or part of the 2025 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
4.75% Senior Unsecured Notes Due 2026 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 500,000,000		$ 500,000,000
Debt instrument interest rate				4.75%		4.75%
Maturity date						Aug. 1, 2026
Redemption description						At any time prior to August 1, 2021, the Company may redeem all or part of the 2026 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
Percentage of aggregate principal amount redeemed						35.00%
Redemption price						104.75%
5.375% Senior Unsecured Notes Due 2027 [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount	$ 500,000,000			$ 500,000,000		$ 500,000,000
Debt instrument interest rate	5.375%			5.375%		5.375%
Maturity date						May 15, 2027
Redemption description						At any time prior to May 15, 2022, the Company may redeem all or part of the 2027 Senior Notes upon not less than 30 nor more than 60 days’ prior notice at a redemption price equal to the sum of (i) 100% of the principal amount thereof, plus (ii) a make-whole premium as of the date of redemption, plus (iii) accrued and unpaid interest and additional interest, if any, thereon, to the date of redemption.
Percentage of aggregate principal amount redeemed						35.00%
Redemption price						105.375%
Net proceeds from borrowing	$ 495,000,000
Senior Notes [Member]
Schedule Of Commitments And Contingencies [Line Items]
Debt instrument principal amount				$ 2,600,000,000		$ 2,600,000,000
Senior Notes and Revolving Credit Facility [Member]
Schedule Of Commitments And Contingencies [Line Items]
Deferred financing fees				$ 27,300,000		$ 27,300,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Senior Unsecured Notes (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2018	May 18, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Principal amount outstanding	$ 2,600,000,000
Carrying value	2,574,616,000		$ 2,078,093,000
Fair Value	$ 2,671,444,000		2,231,097,000
5.25% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Maturity Date	Nov. 15, 2024
Principal amount outstanding	$ 800,000,000
Carrying value	792,760,000		791,880,000
Fair Value	$ 822,680,000		847,064,000
5.75% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Maturity Date	Aug. 15, 2025
Principal amount outstanding	$ 800,000,000
Carrying value	792,754,000		791,967,000
Fair Value	$ 839,824,000		858,848,000
4.75% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Maturity Date	Aug. 1, 2026
Principal amount outstanding	$ 500,000,000
Carrying value	494,749,000		494,246,000
Fair Value	$ 497,290,000		$ 525,185,000
5.375% Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
Maturity Date	May 15, 2027
Principal amount outstanding	$ 500,000,000	$ 500,000,000
Carrying value	494,353,000
Fair Value	$ 511,650,000

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Senior Unsecured Notes (Parenthetical) (Detail)	Sep. 30, 2018	May 18, 2018
5.25% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.25%
5.75% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.75%
4.75% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.75%
5.375% Senior Unsecured Notes Due 2027 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	5.375%	5.375%

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Detail) - USD ($)	Sep. 30, 2018	May 01, 2018	Oct. 26, 2016
2016 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase program authorizing the purchase of shares			$ 750,000,000
Stock repurchase program, remaining authorized repurchase amount		$ 523,100,000
2018 Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Repurchase program authorizing the purchase of shares		$ 1,000,000,000
Stock repurchase program, remaining authorized repurchase amount	$ 1,464,200,000

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			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2018	Sep. 30, 2017
Equity, Class of Treasury Stock [Line Items]
Total Number of Shares Repurchased	259,357	1,042,966	492,175
Open Market Purchases of Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Average Price Paid Per Share				$ 149.82	$ 87.95
Total Number of Shares Repurchased				1,794,000	1,556,000
Dollar Value of Shares Repurchased				$ 268,850	$ 136,850

Shareholders' Equity - Schedu_2

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						9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Stockholders Equity [Abstract]
Dividend declared per common share	$ 0.58	$ 0.38	$ 0.38	$ 0.38	$ 0.28	$ 0.28	$ 1.34	$ 0.94
Cash dividends declared, Amount	$ 52,264	$ 34,254	$ 34,848	$ 34,768	$ 25,710	$ 25,769	$ 121,366	$ 86,247
Cash dividends distributed, Amount	51,764	33,935	34,900	34,403	25,444	25,500	120,599	85,347
Cash dividends deferred, Amount	$ 500	$ 319	$ (52)	$ 365	$ 266	$ 269	$ 767	$ 900

Shareholders' Equity - Summary

Shareholders' Equity - Summary of Activity Related to Shares of Common Stock Issued and Repurchased (Detail) - shares	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2018
Common Stock Outstanding [Line Items]
Beginning balance	88,832,899	89,859,658	90,104,885	90,104,885
Common stock issued and exercise of stock options	23,492	18,944	409,794
Shares withheld for tax withholding and exercises	(3,705)	(3,178)	(162,846)
Shares repurchased under stock repurchase programs	(259,357)	(1,042,966)	(492,175)
Shares issued to directors		441
Ending balance	88,593,329	88,832,899	89,859,658	88,593,329
Common Stock Issued [Member]
Common Stock Outstanding [Line Items]
Beginning balance	129,978,881	129,953,761	129,543,856	129,543,856
Dividend payable/paid	165	117	111
Common stock issued and exercise of stock options	23,492	18,944	409,794
Shares issued to directors		6,059
Ending balance	130,002,538	129,978,881	129,953,761	130,002,538
Treasury Stock [Member]
Common Stock Outstanding [Line Items]
Beginning balance	(41,145,982)	(40,094,103)	(39,438,971)	(39,438,971)
Dividend payable/paid	(165)	(117)	(111)
Shares withheld for tax withholding and exercises	(3,705)	(3,178)	(162,846)
Shares repurchased under stock repurchase programs	(259,357)	(1,042,966)	(492,175)
Shares issued to directors		(5,618)
Ending balance	(41,409,209)	(41,145,982)	(40,094,103)	(41,409,209)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Examination [Line Items]
Provision for income taxes		$ 23,014	$ 35,650	$ 86,854	$ 100,569
Effective tax rate				19.60%	29.60%
Amounts effect on effective tax rate		19,000		$ 19,000
Capital loss carry forward valuation allowance		11,800		11,800
Net adjustment benefit				$ 1,600
Decrease in effective tax rate				3.40%
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				2,006
Maximum [Member]
Income Tax Examination [Line Items]
Tax years under examination				2,017
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
Investor Force [Member]
Income Tax Examination [Line Items]
Valuation allowance recognized		$ 7,800
Financial Engineering Associates Inc [Member]
Income Tax Examination [Line Items]
Valuation allowance recognized	$ 4,000
Accounting Standards Update 2016-09 [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member]
Income Tax Examination [Line Items]
Amount of excess tax benefits recognition				$ 8,800

Segment Information - Additiona

Segment Information - Additional Information (Detail)	9 Months Ended
	Sep. 30, 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		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 357,934	$ 322,097	$ 1,072,296	$ 939,393
Index [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	210,194	184,594	625,042	525,185
Analytics [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	119,898	114,972	358,004	340,759
All Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 27,842	$ 22,531	$ 89,250	$ 73,449

Segment Information - Segment P

Segment Information - Segment Profitability and Reconciliation to Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 195,537	$ 168,738	$ 582,671	$ 485,940
Amortization of intangible assets	11,681	10,614	42,556	32,987
Depreciation and amortization of property, equipment and leasehold improvements	7,453	9,325	23,035	27,322
Operating income	176,403	148,799	517,080	425,631
Other expense (income), net	29,557	27,996	74,473	85,692
Provision for income taxes	23,014	35,650	86,854	100,569
Net income	123,832	85,153	355,753	239,370
Index [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	154,477	134,342	457,923	379,538
Analytics [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	37,046	33,078	106,966	94,483
All Other [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 4,014	$ 1,318	$ 17,782	$ 11,919

Segment Information - Revenue b

Segment Information - Revenue by Geographic Area (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 357,934	$ 322,097	$ 1,072,296	$ 939,393
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	167,415	159,123	498,270	459,958
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	15,118	11,997	43,529	34,949
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	182,533	171,120	541,799	494,907
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	52,997	48,878	159,699	143,140
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	69,602	61,567	218,999	185,655
Europe, the Middle East and Africa ("EMEA") [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	122,599	110,445	378,698	328,795
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	16,572	13,577	48,941	39,640
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	36,230	26,955	102,858	76,051
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating revenues	$ 52,802	$ 40,532	$ 151,799	$ 115,691

Segment Information - Long-Live

Segment Information - Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 1,917,192	$ 1,976,894
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,805,085	1,847,605
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	3,507	1,685
Total Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	1,808,592	1,849,290
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	82,004	94,782
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	18,750	22,394
Total EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	100,754	117,176
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	318	432
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	7,528	9,996
Total Asia & Australia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 7,846	$ 10,428

Divestitures - Additional Infor

Divestitures - Additional Information (Detail) - USD ($) $ in Thousands	Oct. 12, 2018	Jul. 25, 2018	Apr. 09, 2018	Sep. 30, 2018
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from divestiture				$ 21,010
Gain on divestiture				$ 12,055
Financial Engineering Associates Inc [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from divestiture			$ 21,000
Goodwill			2,900
Amortized identifiable intangible assets			2,700
Other net assets			6,100
Cash costs			1,400
Gain on divestiture			$ 10,600
Investor Force [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from divestiture		$ 62,000
Investor Force [Member] | Subsequent Events [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Cash received from divestiture	$ 62,800
Estimates pre-tax gain of divestiture	47,000
Estimates after-tax gain of divestiture	$ 41,000

Divestitures - Carrying Amounts

Divestitures - Carrying Amounts of Major Classes of Assets and Liabilities (Detail) $ in Thousands	Sep. 30, 2018USD ($)
ASSETS
Total current assets	$ 18,995
LIABILITIES
Total current liabilities	5,234
Investor Force [Member]
ASSETS
Accounts receivable	4,427
Prepaid and other assets	182
Total current assets	4,609
Property, equipment and leasehold improvements (net of accumulated depreciation and amortization of $543)	47
Goodwill	8,691
Intangible assets (net of accumulated amortization of $5,068)	4,032
Other non-current assets	24
Deferred tax assets	1,592
Total non-current assets	14,386
Assets held-for-sale	18,995
LIABILITIES
Accrued compensation and related benefits	810
Other accrued liabilities	108
Deferred revenue	4,316
Total current liabilities	5,234
Liabilities held-for-sale	$ 5,234

Divestitures - Carrying Amoun_2

Divestitures - Carrying Amounts of Major Classes of Assets and Liabilities (Parenthetical) (Detail) - Investor Force [Member] $ in Thousands	Sep. 30, 2018USD ($)
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Property, equipment and leasehold improvements, accumulated depreciation and amortization	$ 543
Intangible assets, accumulated amortization	$ 5,068

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Oct. 30, 2018	Oct. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2018	Sep. 30, 2017
Subsequent Event [Line Items]
Quarterly dividend declared			$ 0.58	$ 0.38	$ 0.38	$ 0.38	$ 0.28	$ 0.28	$ 1.34	$ 0.94
Total number of shares repurchased			259,357	1,042,966	492,175
Value of share repurchased									$ 292,970	$ 150,350
Subsequent Events [Member]
Subsequent Event [Line Items]
Quarterly dividend declared	$ 0.58
Quarterly dividend declared date	Oct. 30, 2018
Quarterly dividend payable date	Nov. 30, 2018
Quarterly dividend record date	Nov. 16, 2018
Total number of shares repurchased		800,000
Average price paid per share		$ 153.92
Value of share repurchased		$ 119,600