Moody's (MCO) 10-Q 2 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information shares in Millions	3 Months Ended
	Mar. 31, 2019shares
Document Documentand Entity Information [Abstract]
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Registrant Name	MOODYS CORP /DE/
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Fiscal Year Focus	2019
Trading Symbol	MCO
Document Period End Date	Mar. 31, 2019
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Central Index Key	0001059556
Entity Common Stock Shares Outstanding	189.6

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)
Revenues	$ 1,142.1	$ 1,126.7
Expenses
Operating	341.7	314.9
Selling, general and administrative	281.5	271.1
Restructuring Charges	5.5
Depreciation and amortization	50.3	49.1
Acquisition-Related Expenses	1.4	0.8
Total expenses	680.4	635.9
Operating Income	461.7	490.8
Non-operating (expense) income, net
Interest expense, net	(52.5)	(50.7)
Other non-operating income, net	2.3	1
Total non-operating (expense) income, net	(50.2)	(49.7)
Income before provisions for income taxes	411.5	441.1
Provision for income taxes	37.9	64.3
Net income	373.6	376.8
Less: Net income attributable to noncontrolling interests	0.7	3.9
Net income attributable to Moody's	$ 372.9	$ 372.9
Earnings per share attributable to Moody's common shareholders
Basic	$ 1.96	$ 1.95
Diluted	$ 1.93	$ 1.92
Weighted average number of shares outstanding
Basic	190.4	191.4
Diluted	192.8	194.5

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)
Net income	$ 373.6	$ 376.8
Foreign currency translation:
Foreign currency translation adjustments - Pre Tax	(26.7)	136.1
Foreign currency translation adjustments - Net of Tax	(26.7)	136.1
Net gains (losses) on net investment hedges - Pre Tax	30.4	(14.5)
Net gains (losses) on net investment hedges, Tax	(6.9)	3.6
Net gains (losses) on net investment hedges, Net of Tax	23.5	(10.9)
Cash flow hedges:
Net realized and unrealized gain (loss) on cash flow hedges - Pre Tax		1.9
Net realized and unrealized gain (loss) on cash flow hedges - Tax Amount		(0.4)
Net realized and unrealized gain (loss) on cash flow hedges - Net of Tax		1.5
Reclassification of losses included in net income - Pre Tax		(0.1)
Reclassification of losses included in net income- Net of Tax		(0.1)
Pension and Other Retirement Benefits:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	0.8	1.4
Amortization of actuarial losses and prior service costs included in net income - Tax	(0.2)	(0.4)
Amortization of actuarial losses and prior service costs included in net income - Net of Tax	0.6	1
Net actuarial losses and prior service costs - Pre Tax	1.1
Net actuarial losses and prior service costs - Tax	(0.3)
Net actuarial losses and prior service costs - Net of Tax	0.8
Total other comprehensive (loss) income - Pre Tax	5.6	124.8
Total other comprehensive (loss)income - Tax	(7.4)	2.8
Total other comprehensive (loss) income - Net of Tax	(1.8)	127.6
Comprehensive income	371.8	504.4
Less: Comprehensive income attributable to noncontrolling interests and redeemable noncontrolling interest	8.2	8.9
Comprehensive income attributable to Moody's	$ 363.6	$ 495.5

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 1,196.6	$ 1,685
Short-term investments	114	132.5
Accounts receivable, net of allowances of $46.0 in 2019 and $43.5 in 2018	1,301.2	1,287.1
Other current assets	286.6	282.3
Total current assets	2,898.4	3,386.9
Property and equipment, net of accumulated depreciation of $834.9 in 2019 and $790.2 in 2018	318.7	320.4
Operating lease right-of-use assets	508.1
Goodwill	3,762.5	3,781.3
Intangible assets, net	1,530.4	1,566.1
Deferred tax assets, net	178.8	197.2
Other assets	321.2	274.3
Total assets	9,518.1	9,526.2
Current liabilities:
Accounts payable and accrued liabilities	537.1	695.2
Current portion of operating lease liabilities	87.4
Commercial paper	318.8
Current portion of long-term debt		449.9
Deferred revenue	1,062.3	953.4
Total current liabilities	2,005.6	2,098.5
Non-current portion of deferred revenue	120.9	122.3
Long-term debt	5,228.6	5,226.1
Deferred tax liabilities, net	353.4	351.7
Uncertain tax positions	474.5	494.6
Operating lease liabilities	523.5
Other liabilities	486.6	576.5
Total liabilities	9,193.1	8,869.7
Contingencies (Note 19)
Shareholders' equity:
Preferred stock, par value $.01 per share; 10,000,000 shares authorized; no shares issued and outstanding
Common stock	3.4	3.4
Capital surplus	435.7	600.9
Retained earnings	8,893.6	8,594.4
Treasury stock, at cost; 153,299,621 and 151,598,695 shares of common stock at March 31, 2019 and December 31, 2018, respectively	(8,754)	(8,312.5)
Accumulated other comprehensive loss	(455.5)	(426.3)
Total Moody's shareholders' deficit	123.2	459.9
Noncontrolling interests	201.8	196.6
Total shareholders' deficit	325	656.5
Total liabilities and shareholders' (deficit) equity	9,518.1	9,526.2
Series common stock
Shareholders' equity:
Common stock

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Accounts receivable, allowances	$ 46	$ 43.5
Property and equipment, accumulated depreciation	$ 834.9	$ 790.2
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	342,902,272	342,902,272
Treasury stock, shares	153,299,621	151,598,695
Series common stock
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	0	0

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net income	$ 373.6	$ 376.8
Reconciliation of net income to net cash provided by operating activities:
Depreciation and amortization	50.3	49.1
Stock-based compensation expense	35.7	35.1
Deferred income taxes	13.8	(4.2)
Changes in assets and liabilities:
Accounts receivable	(8.5)	(29.9)
Other current assets	(5.9)	47.8
Other assets	(13.5)	(14.5)
Accounts payable and accrued liabilities	(179.5)	(224.1)
Restructuring	(2.5)	(0.1)
Deferred revenue	103.9	167.7
Unrecognized tax benefits and other non-current tax liabilities	(21.9)	(17.9)
Other liabilities	21.6	5.7
Net cash provided by (used in) operating activities	367.1	391.5
Cash flows from investing activities
Capital additions	(20)	(15)
Purchases of investments	(37.8)	(50.3)
Sales and maturities of short-term investments	50.6	41.1
Cash received upon diposal of a subsidiary, net of cash transferred to purchaser		5.7
Net cash used in investing activities	(7.2)	(18.5)
Cash flows from financing activities
Repayments of notes	(450)
Issuance of commercial paper	402.8	219.6
Repayments of commercial paper	(85)	(259.6)
Proceeds from stock-based compensation plans	14.2	28.5
Repurchase of shares related to stock-based compensation	(50.6)	(42)
Treasury shares	(448.2)	(43.4)
Cash paid for ASR contract relating to shares retained by counterparty until final settlement	(125.3)
Dividends	(94.4)	(84.1)
Dividends to noncontrolling interests		(1.1)
Payment for noncontrolling interest	(12.3)
Debt issuance costs, extinguishment costs and related fees		(0.2)
Net cash provided (used in) by financing activities	(848.8)	(182.3)
Effect of exchange rate changes on cash and cash equivalents	0.5	15.1
Net increase (decrease) in cash and cash equivalents	(488.4)	205.8
Cash and cash equivalents, beginning of the period	1,685	1,071.5
Cash and cash equivalents, end of the period	$ 1,196.6	$ 1,277.3

CONSOLIDATED STATEMENT OF SHARE

CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Total Moody's Shareholders' Equity (Deficit)	Noncontrolling Interests
Beginning Balance (in shares) at Dec. 31, 2017		342.9			(151.9)
Beginning Balance at Dec. 31, 2017	$ (114.9)	$ 3.4	$ 528.6	$ 7,465.4	$ (8,152.9)	$ (172.2)	$ (327.7)	$ 212.8
Net income	376.8			372.9			372.9	3.9
Dividends	(85.1)			(83.7)			(83.7)	(1.4)
Stock-based compensation	35.2		35.2				35.2
Shares issued for stock-based compensation plans, net	(32.3)		(57.2)		$ 24.9		(32.3)
Shares issued for stock-based compensation plans, net (in shares)					1.2
Treasury shares repurchased, shares					(0.3)
Treasury shares repurchased	(43.4)				$ (43.4)		(43.4)
Currency translation adjustment	125.2					120.2	120.2	5
Amortization of actuarial losses and prior service costs included in net income - Net of Tax	1					1	1
Net realized and unrealized gain on cash flow hedges (net of tax of $1.1 million)	1.4					1.4	1.4
Ending Balance at Mar. 31, 2018	420	$ 3.4	506.6	7,913	$ (8,171.4)	(51.9)	199.7	220.3
Ending Balance (in shares) at Mar. 31, 2018		342.9			(151)
Adoption of new ASU | New Revenue Accounting Standard [Member]	156.1			156.1			156.1
Adoption of new ASU | Accounting Standards Update 2016-01 [Member]				2.3		(2.3)
Beginning Balance (in shares) at Dec. 31, 2018		342.9			(151.6)
Beginning Balance at Dec. 31, 2018	656.5	$ 3.4	600.9	8,594.4	$ (8,312.5)	(426.3)	459.9	196.6
Net income	373.6			372.9			372.9	0.7
Dividends	(93.7)			(93.5)			(93.5)	(0.2)
Cash paid for ASR contract relating to shares retained by counterparty until final settlement	(125.3)		(125.3)				(125.3)
Stock-based compensation	35.8		35.8				35.8
Shares issued for stock-based compensation plans, net	(59.6)		(66.3)		$ 6.7		(59.6)
Shares issued for stock-based compensation plans, net (in shares)					1
Purchase of noncontrolling interest	(12.3)		(9.4)				(9.4)	(2.9)
Treasury shares repurchased, shares					(2.7)
Treasury shares repurchased	(448.2)				$ (448.2)		(448.2)
Currency translation adjustment	(3.2)					(10.8)	(10.8)	7.6
Net actuarial losses and prior service costs - Net of Tax	0.8					0.8	0.8
Amortization of actuarial losses and prior service costs included in net income - Net of Tax	0.6					0.6	0.6
Ending Balance at Mar. 31, 2019	$ 325	$ 3.4	$ 435.7	8,893.6	$ (8,754)	(455.5)	$ 123.2	$ 201.8
Ending Balance (in shares) at Mar. 31, 2019		342.9			(153.3)
Adoption of new ASU | Accounting Standards Update 2018-02 [Member]				$ 19.8		$ (19.8)

CONSOLIDATED STATEMENT OF SHA_2

CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (DEFICIT) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Stockholders Equity (Unaudited) [Abstract]
Dividends declared per share attributable to Moody's common shareholders	$ 0.5	$ 0.44
Currency translation adjustment, tax	$ 6.9	$ (3.6)
Net actuarial losses and prior service costs - Tax	0.3
Amortization of actuarial losses and prior service costs included in net income - Tax	$ 0.2	0.4
Net unrealized gain on cash flow hedges, tax		$ 0.4

GLOSSARY OF TERMS AND ABBREVIAT

GLOSSARY OF TERMS AND ABBREVIATIONS	3 Months Ended
	Mar. 31, 2019
Glossary of Terms and Abbreviations [Abstract]
GLOSSARY OF TERMS AND ABBREVIATIONS	GLOSSARY OF TERMS AND ABBREVIATIONS The following terms, abbreviations and acronyms are used to identify frequently used terms in this report: TERM DEFINITION Acquisition-Related Amortization Amortization of definite-lived intangible assets acquired by the Company from all business combination transactions Acquisition-Related Expenses Consists of expenses incurred to complete and integrate the acquisition of Bureau van Dijk for which the integration will be a multi-year effort Adjusted Diluted EPS Diluted EPS excluding the impact of certain items as detailed in the section entitled “Non-GAAP Financial Measures” Adjusted Net Income Net Income excluding the impact of certain items as detailed in the section entitled “Non-GAAP Financial Measures” Adjusted Operating Income Operating income excluding depreciation and amortization Adjusted Operating Margin Adjusted Operating Income divided by revenue Americas Represents countries within North and South America, excluding the U.S. AOCI Accumulated other comprehensive income (loss); a separate component of shareholders’ equity (deficit) ASC The FASB Accounting Standards Codification; the sole source of authoritative GAAP as of July 1, 2009 except for rules and interpretive releases of the SEC, which are also sources of authoritative GAAP for SEC registrants Asia-Pacific Represents Australia and countries in Asia including but not limited to: China, India, Indonesia, Japan, Korea, Malaysia, Singapore, Sri Lanka and Thailand ASR Accelerated Share Repurchase ASU The FASB Accounting Standards Update to the ASC. It also provides background information for accounting guidance and the bases for conclusions on the changes in the ASC. ASUs are not considered authoritative until codified into the ASC Board The board of directors of the Company BPS Basis points Brexit The withdrawal of the United Kingdom from the European Union Bureau van Dijk Bureau van Dijk Electronic Publishing, B.V.; a global provider of business intelligence and company information; acquired by the Company on August 10, 2017 via the acquisition of Yellow Maple I B.V., an indirect parent of Bureau van Dijk CECL Current expected credit losses CFG Corporate finance group; an LOB of MIS CLO Collateralized loan obligation CMBS Commercial mortgage-backed securities; an asset class within SFG Common Stock The Company’s common stock Company Moody’s Corporation and its subsidiaries; MCO; Moody’s Content A reporting unit within the MA segment that offers subscription based research, data and analytical products, including credit ratings produced by MIS, credit research, quantitative credit scores and other analytical tools, economic research and forecasts, business intelligence and company information products, and commercial real estate data and analytical tools CP Commercial Paper CP Program A program entered into on August 3, 2016 allowing the Company to privately place CP up to a maximum of $1 billion for which the maturity may not exceed 397 days from the date of issue and which is backstopped by the 2018 Facility CRAs Credit rating agencies D&A Depreciation and amortization DBPPs Defined benefit pension plans EMEA Represents countries within Europe, the Middle East and Africa EPS Earnings per share ERS Enterprise Risk Solutions; an LOB within MA, which offers risk management software solutions as well as related risk management advisory engagements services ESG Environmental, Social, and Governance ESMA European Securities and Markets Authority ETR Effective tax rate EU European Union EUR Euros EURIBOR The Euro Interbank Offered Rate Excess Tax Benefits The difference between the tax benefit realized at exercise of an option or delivery of a restricted share and the tax benefit recorded at the time the option or restricted share is expensed under GAAP Exchange Act The Securities Exchange Act of 1934, as amended External Revenue Revenue excluding any intersegment amounts FASB Financial Accounting Standards Board FIG Financial institutions group; an LOB of MIS Financial Reform Act Dodd-Frank Wall Street Reform and Consumer Protection Act Free Cash Flow Net cash provided by operating activities less cash paid for capital additions FSTC Financial Services Training and Certifications; now referred to as MALS FX Foreign exchange GAAP U.S. Generally Accepted Accounting Principles GBP British pounds ICRA ICRA Limited; a leading provider of credit ratings and research in India, for which the Company owns approximately 52% IRS Internal Revenue Service IT Information technology KIS Korea Investors Service, Inc; a leading Korean rating agency and consolidated subsidiary of the Company KIS Pricing Korea Investors Service Pricing, Inc; a leading Korean provider of fixed income securities pricing and consolidated subsidiary of the Company KIS Research Korea Investors Service Research; a Korean provider of financial research and consolidated subsidiary of the Company Korea Republic of South Korea LIBOR London Interbank Offered Rate LOB Line of business M&A Mergers and acquisitions MA Moody’s Analytics – a reportable segment of MCO; provides a wide range of products and services that support financial analysis and risk management activities of institutional participants in global financial markets; consists of three LOBs – RD&A, ERS and PS MAKS Moody’s Analytics Knowledge Services; formerly known as Copal Amba; provides offshore research and analytic services to the global financial and corporate sectors; part of the PS LOB and a reporting unit within the MA reportable segment MALS Moody’s Analytics Learning Solutions; a reporting unit within the MA segment that includes on-line and classroom-based training services as well as credentialing and certification services; formerly known as FSTC MCO Moody’s; Moody’s Corporation and its subsidiaries; the Company MD&A Management’s Discussion and Analysis of Financial Condition and Results of Operations MIS Moody’s Investors Service – a reportable segment of MCO; consists of five LOBs – SFG, CFG, FIG, PPIF and MIS Other MIS Other Consists of non-ratings revenue from ICRA, KIS Pricing and KIS Research. These businesses are components of MIS; MIS Other is an LOB of MIS Moody’s Moody’s Corporation and its subsidiaries; MCO; the Company Net Income Net income attributable to Moody’s Corporation, which excludes net income from consolidated noncontrolling interests belonging to the minority interest holder New Lease Accounting Standard Updates to the ASC pursuant to ASU No. 2016-02, “Leases (ASC Topic 842)”. This new accounting guidance requires lessees to recognize a right-of-use asset and lease liability on the balance sheet for all leases with terms of more than 12 months. Recognition, measurement and presentation of expenses and cash flows depend on classification as either a finance or operating lease New Revenue Accounting Standard Updates to the ASC pursuant to ASU No. 2014-09, “Revenue from Contracts with Customers (ASC Topic 606)”. This new accounting guidance significantly changes the accounting framework under U.S. GAAP relating to revenue recognition and to the accounting for the deferral of incremental costs of obtaining or fulfilling a contract with a customer NM Percentage change is not meaningful Non-GAAP A financial measure not in accordance with GAAP; these measures, when read in conjunction with the Company’s reported results, can provide useful supplemental information for investors analyzing period-to-period comparisons of the Company’s performance, facilitate comparisons to competitors’ operating results and to provide greater transparency to investors of supplemental information used by management in its financial and operational decision making NRSRO Nationally Recognized Statistical Rating Organization, which is a credit rating agency registered with the SEC. OCI Other comprehensive income (loss); includes gains and losses on cash flow and net investment hedges, unrealized gains and losses on available for sale securities (in periods prior to January 1, 2018), certain gains and losses relating to pension and other retirement benefit obligations and foreign currency translation adjustments Omega Performance A leading provider of online credit training, acquired by the Company in August 2018 Operating segment Term defined in the ASC relating to segment reporting; the ASC defines an operating segment as a component of a business entity that has each of the three following characteristics: i) the component engages in business activities from which it may recognize revenue and incur expenses; ii) the operating results of the component are regularly reviewed by the entity’s chief operating decision maker; and iii) discrete financial information about the component is available Other Retirement Plans The U.S. retirement healthcare and U.S. retirement life insurance plans PPIF Public, project and infrastructure finance; an LOB of MIS Profit Participation Plan Defined contribution profit participation plan that covers substantially all U.S. employees of the Company PS Professional Services, an LOB within MA consisting of MAKS and MALS that provides offshore analytical and research services as well as learning solutions and certification programs RD&A Research, Data and Analytics; an LOB within MA that offers subscription based research, data and analytical products, including credit ratings produced by MIS, credit research, quantitative credit scores and other analytical tools, economic research and forecasts, business intelligence and company information products, and commercial real estate data and analytical tools Reform Act Credit Rating Agency Reform Act of 2006 REIT Real Estate Investment Trust Reis, Inc. (Reis) A leading provider of U.S. commercial real estate (CRE) data; acquired by the Company in October 2018 Relationship Revenue For MIS, represents recurring monitoring fees of a rated debt obligation and/or entities that issue such obligations, as well as revenue from programs such as commercial paper, medium-term notes and shelf registrations. For MIS Other represents subscription-based revenue. For MA, represents subscription-based revenue and software maintenance revenue Reporting unit The level at which Moody’s evaluates its goodwill for impairment under U.S. GAAP; defined as an operating segment or one level below an operating segment RMBS Residential mortgage-backed securities; an asset class within SFG ROU Asset Assets recorded pursuant to the New Lease Accounting Standard which represent the Company’s right to use an underlying asset for the term of a lease SaaS Software-as-a-Service SEC U.S. Securities and Exchange Commission Securities Act Securities Act of 1933, as amended SFG Structured finance group; an LOB of MIS SG&A Selling, general and administrative expenses Tax Act The “Tax Cuts and Jobs Act” enacted into U.S. law on December 22, 2017, which significantly amends the tax code in the U.S. Total Debt All indebtedness of the Company as reflected on the consolidated balance sheets Transaction Revenue For MIS, represents the initial rating of a new debt issuance as well as other one-time fees. For MIS Other, represents revenue from professional services as well as data services, research and analytical engagements. For MA, represents perpetual software license fees and revenue from software implementation services, risk management advisory projects, training and certification services, and research and analytical engagements U.K. United Kingdom U.S. United States USD U.S. dollar UTPs Uncertain tax positions Vigeo Eiris A global leader in ESG research, data and assessments, acquired by the Company on April 11, 2019. 2010 Indenture Supplemental indenture and related agreements dated August 19, 2010, relating to the 2010 Senior Notes 2010 Senior Notes Principal amount of $500 million, 5.50% senior unsecured notes due in September 2020 pursuant to the 2010 Indenture 2012 Indenture Supplemental indenture and related agreements dated August 18, 2012, relating to the 2012 Senior Notes 2012 Senior Notes Principal amount of $500 million, 4.50% senior unsecured notes due in September 2022 pursuant to the 2012 Indenture 2013 Indenture Supplemental indenture and related agreements dated August 12, 2013, relating to the 2013 Senior Notes 2013 Senior Notes Principal amount of the $500 million, 4.875% senior unsecured notes due in February 2024 pursuant to the 2013 Indenture 2014 Indenture Supplemental indenture and related agreements dated July 16, 2014, relating to the 2014 Senior Notes 2014 Senior Notes (5-Year) Principal amount of $450 million, 2.75% senior unsecured notes due in July 2019 pursuant to the 2014 Indenture; repaid in 2019 2014 Senior Notes (30-Year) Principal amount of $600 million, 5.25% senior unsecured notes due in July 2044 pursuant to the 2014 Indenture 2015 Facility Five-year unsecured revolving credit facility, with capacity to borrow up to $1 billion; backstops CP issued under the CP Program 2015 Indenture Supplemental indenture and related agreements dated March 9, 2015, relating to the 2015 Senior Notes 2015 Senior Notes Principal amount of €500 million, 1.75% senior unsecured notes issued March 9, 2015 pursuant to the 2015 Indenture; repaid in 2018 2017 Floating Rate Senior Notes Principal amount of $300 million, floating rate senior unsecured notes due in September 2018 pursuant to the 2017 Indenture 2017 Indenture Collectively the Supplemental indenture and related agreements dated March 2, 2017, relating to the 2017 Floating Rate Senior Notes and 2017 Notes Due 2023 and 2028, and the supplemental indenture and related agreements dated June 12, 2017, relating to the 2017 Notes Due 2023 and 2028 2017 Senior Notes Due 2023 Principal amount of $500 million, 2.625% senior unsecured notes due January 15, 2023 pursuant to the 2017 Indenture 2017 Senior Notes Due 2028 Principal amount of $500 million, 3.25% senior unsecured notes due January 15, 2028 pursuant to the 2017 Indenture 2017 Senior Notes Due 2021 Principal amount of $500 million, 2.75% senior unsecured notes due in December 2021 2018 Facility Five-year unsecured revolving credit facility, with capacity to borrow up to $1 billion; replaced the 2015 Facility; backstops CP issued under the CP Program 2018 Senior Notes Principal amount of $300 million, 3.25% senior unsecured notes due June 7, 2021 2018 Senior Notes (10-year) Principal amount of $400 million, 4.25% senior unsecured notes due February 1, 2029 2018 Senior Notes (30-year) Principal amount of $400 million, 4.875% senior unsecured notes December 17, 2048

DESCRIPTION OF BUSINESS AND BAS

DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2019
Description of Business and Basis of Presentation [Abstract]
DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION	NOTE 1 . DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION Moody’s is a provider of (i) credit ratings; (ii) credit, capital markets and economic research, data and analytical tools; (iii) software solutions that support financial risk management activities; (iv) quantitatively derived credit scores; (v) learning solutions and certification services ; (vi) offshore financial research and analytical services; and (vii) company information and business intelligence products. Moody’s reports in two r eportable segments: MIS and MA. MIS, the credit rating agency, publishes credit ratings on a wide range of debt obligations and the entities that issue such obligations in markets worldwide. Revenue is primarily derived from the originators and issuers of such transactions who use MIS ratings in the distribution of their debt issues to investors. Additionally, MIS earns revenue from certain non-ratings-related operations which consist primarily of financial instrument pricing services in the Asia-Pacific region as well as revenue from ICRA’s non-ratings operations. The revenue from these operations is included in the MIS Other LOB and is not material to the results of the MIS segment. MA provides financial intelligence and analytical tools to assist businesses in making decisions. MA’s portfolio of solutions consists of specialized research, data, software, and professional services, which are assembled to support the financial analysis and risk management activities of institutional customers worldwide. These interim financial statements have been prepared in accordance with the instructions to Form 10-Q and sh ould be read in conjunction with the Company’s consolidated financial statements and related notes in the Company’s 2018 annual report on Form 10-K filed with the SEC on February 22, 2019 . The results of interim periods are not necessarily indicati ve of results for the full year or any subsequent period. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation of financial position, results of operations and cash flows at the da tes and for the periods presented have been included. The year-end consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by accounting principles generally accepted in the United States of America. Certain reclassifications have been made to prior period amounts to conform to the current presentation. Adoption of New Accounting Standard s On January 1, 2019 , the Company adopted ASU No. 2016-02, “Leases (Topic 842)” and has elected to apply the provisions of the New Lease Accounting Standard on the date of adoption with adjustments to the assets and liabilities on its opening balance sheet, with no cumulative-effect adjustment to the opening balance of retained earnings required. A ccor dingly, the Company will not restate prior year comparative periods for the impact of the New Lease Accounting Standard . T he New Lease Accounting Standard requir es lessees to recognize a n ROU A sset and lease liability for all leases with terms of more than 12 months. The Company has elected the package of practical expedients permitted under the transition guidance within the New Lease Accounting Standard , which permits the Company not to reassess the following for any expired or existing contracts: i) wheth er any contracts contain leases; ii) lease classification (i.e. operating lease or finance/capital lease); and iii) initial direct costs. The adoption of the New Lease Accounting Standard result ed in the recognition of an ROU Assets and lease liabilities of a pproximately $ 5 18 million and $ 6 22 million, respectively, at January 1, 2019, consisting primarily of operating leases relating to office space . Pursuant to this transition adjustment, the Company also recogniz ed approximately $ 150 million and approximatel y $ 125 million in additional deferred tax assets and liabilities, respectively. Compared to previous guidance, the New Lease Accounting Standard does not significantly change the method by which a lessee should recognize, measure and present expenses and c ash flows arising from a lease . Refer to Note 2 for a more fulsome description of the Company’s accounting policy relating to the New Lease Accounting Standard, which includes a discussion relating to the pattern of operating lease expense recognition (bo th prior to and subsequent to an impairment of a ROU Asset). In the first quarter of 2019 , the Company adopted ASU No. 2018-02, “Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Co mp rehensive Income”. Under current GAAP, adjustments to deferred tax assets and liabilities related to a change in tax laws or rates are included in income from continuing operations, even in situations where the related items were originally recognized in OCI (commonly referred to as a “stranded tax effect”). The provisions of this ASU permit the reclassification of the stranded tax effect related to the Tax Act from AOCI to retained earnings. In the first quarter of 2019, t he Company reclassified approximately $ 20 million of tax benefits from AOCI to retained earnings relating to the aforementioned stranded tax effect of the Tax Act. On January 1, 2019 , the Company adopted ASU No. 2018-16, “Derivatives and Hedging (Topic 815): Inclusion of the Sec ured Overnight Financing Rate (SOFR) Overnight Index Swap (OIS) Rate as a Benchmark Interest Rate for Hedge Accounting Purposes”. The amendments in this ASU permit the use of the OIS rate based on SOFR as a U.S. benchmark interest rate for hedge accountin g purposes under ASC 815, in addition to the currently permissible benchmark interest rates. T his ASU provide s the Company the ability to utilize the OIS rate based on SOFR as the benchmark interest rate on certain hedges of interest rate risk. The adopti on of this ASU had no impact on the Company’s financial statements upon adoption . Reclassification of Previously Reported Revenue by LOB There were certain organizational/product realignments in both MIS and MA in the first quarter of 2019. Accordingly, in MIS, revenue from REITs, which was previously classified in the SFG LOB, is now classified in the CFG LOB. In MA, revenue relating to the Bureau van Dijk FACT product ( a credit assessment and origination solution ), which was previously classified in RD&A, is now classified in the ERS LOB. Accordingly, 2018 revenue by LOB was reclassified to co nform with this new presentation , as follows: MIS As previously reported Reclassification As Reclassified MA As previously reported Reclassification As Reclassified CFG RD&A Q1 $ 377.7 $ 11.9 $ 389.6 Q1 $ 269.2 $ (2.1) $ 267.1 Q2 377.6 13.4 391.0 Q2 279.9 (4.0) 275.9 Q3 296.1 11.2 307.3 Q3 282.6 (2.3) 280.3 Q4 282.7 8.6 291.3 Q4 302.4 (5.3) 297.1 Full year 2018 $ 1,334.1 $ 45.1 $ 1,379.2 Full year 2018 $ 1,134.1 $ (13.7) $ 1,120.4 SFG ERS Q1 $ 129.7 $ (11.9) $ 117.8 Q1 $ 100.1 $ 2.1 $ 102.2 Q2 141.6 (13.4) 128.2 Q2 105.5 4.0 109.5 Q3 125.4 (11.2) 114.2 Q3 113.0 2.3 115.3 Q4 129.8 (8.6) 121.2 Q4 118.8 5.3 124.1 Full year 2018 $ 526.5 $ (45.1) $ 481.4 Full year 2018 $ 437.4 $ 13.7 $ 451.1

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2019
Summary of Significant Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	NOTE 2 . SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES On January 1, 2019, the Company adopted the New Lease Accounting Standard as more fully discussed in Note 1. Accordingly, the Company revised its lease accounting policy to reflect the provisions of the new standard, which is discussed below. All other significant accounting policies described in the Form 10-K for the year ended December 31, 201 8 remain unchanged. Additionally, refer to Note 18 for additional disclosures relating to the Company’s lease obligations . Leases The Company has operating leases , of which substantially all relate to the lease of office space. The Company’s leases which are classifie d as finance leases are not material to the condensed consolidated financial statements. The Company determines if an arrangement meets the definition of a lease at contract inception. The Company recognizes i n its consolidated balance she et a lease liability and an ROU A sset for all leases with a lease term greater than 12 months. In determining the length of the lease term, the Company utilizes judgment in assess ing the likelihood of whether it is reasonably certain that it will exercise an option to extend or early-terminate a lease, if such options are pr ovided in the lease agreement. ROU A ssets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. ROU A ssets and lease liabilities are recognized at the lease commencem ent date based on the present value of lease payments over the lease term. As substantially all of the Company’s leases do not provide an implicit interest rate, the Company uses its estimated secured incremental borrowing rates at the lease commencement d ate in determining the present value of lease payments. These secured incremental borrowing rates are attributable to the currency in which the lease is denominated. At commencement, the Company’s initial measurement of the ROU A sset is calculated as the p resent value of the remaining lease payments (i.e., lease liability), with additive adjustments reflecting: initial direct costs (e . g ., broker commissions) and prepaid lease payments (if any) ; and reduced by any lease incentives provided by the lessor if: ( i) received before lease commencement or ( ii ) receipt of the lease incentive is cont ingent upon future events for which the occurrence is both probable an d within the Company’s control. Lease expense for minimum operating lease payments is recognized on a straight-line basis over the lease term. This straight-line lease expense represents a single lease cost which is comprised of both an interest accretion component relating to the lease liability and amortization of the ROU Assets. The Company records thi s single lease cost in operating and SG&A expenses. However, in situations where an operating lease ROU A sset has been impaired, the subsequent amortizatio n of the ROU Asset is then recorded on a straight-line basis over the remaining lease term and is com bined with accretion expense on the lease liability to result in single operating lease cost (which subsequent to impairment will no longer follow a straight-line recognition pattern) . The Company has lease agreements which include lease and non-lease comp onents. For the Company’s office space leases, the lease components (e.g., fixed rent payments) and non-lease components (e.g., fixed common-area maintenance costs) are combined and accounted fo r as a single lease component. Variable lease payments (e.g. v ariable common-area-maintenance costs) are only included in the initial measurement of the lease liability to the extent those payments depend on an index or a rate. Variable lease payments not included in the lease liability are recognized in net income i n the period in which the obligation for those payments is incurred.

REVENUES

REVENUES	3 Months Ended
	Mar. 31, 2019
Revenues [Abstract]
REVENUES	NOTE 3 . REVENUES Revenue by Category The following table presents the Company’s revenues disaggregated by LOB: Three Months Ended March 31, 2019 2018 MIS: Corporate finance (CFG) (1) Investment-grade $ 97.4 $ 87.2 High-yield 57.3 57.9 Bank loans 72.6 110.1 Other accounts (2) 128.1 134.4 Total CFG 355.4 389.6 Structured finance (SFG) (1) Asset-backed securities 23.2 28.2 RMBS 23.5 24.3 CMBS 17.7 21.3 Structured credit 35.2 43.4 Other accounts 1.1 0.6 Total SFG 100.7 117.8 Financial institutions (FIG) Banking 79.6 77.0 Insurance 29.0 28.3 Managed investments 4.0 5.7 Other accounts 3.2 3.3 Total FIG 115.8 114.3 Public, project and infrastructure finance (PPIF) Public finance / sovereign 46.2 46.9 Project and infrastructure 46.5 46.3 Total PPIF 92.7 93.2 Total ratings revenue 664.6 714.9 MIS Other 5.5 5.0 Total external revenue 670.1 719.9 Intersegment royalty 32.3 29.8 Total MIS 702.4 749.7 MA: Research, data and analytics (RD&A) (3) 307.7 267.1 Enterprise risk solutions (ERS) (3) 121.9 102.2 Professional services (PS) 42.4 37.5 Total external revenue 472.0 406.8 Intersegment revenue 2.4 5.0 Total MA 474.4 411.8 Eliminations (34.7) (34.8) Total MCO $ 1,142.1 $ 1,126.7 (1) Pursuant to certain organizational realignments in the first quarter of 2019, MIS now reports revenue from REITs, which was previously classified in the SFG LOB, as a component of the CFG LOB. The amounts reclassified were not material and prior year revenue by LOB has been reclassified to conform to this new presentation. (2) Other includes: recurring monitoring fees of a rated debt obligation and/or entities that issue such obligations as well as fees from programs such as commercial paper, medium term notes, and ICRA corporate finance revenue. (3) Pursuant to organizational/product realignments in the first quarter of 2019, revenue relating to the Bureau van Dijk FACT product, a credit assessment and origination software solution, is now reported in the ERS LOB. This revenue was previously reported in the RD&A LOB. Prior year revenue by LOB has been reclassified to conform to this new presentation, and the amounts reclassified were not material. The following table presents the Company’s revenues disaggregated by LOB and geographic area: Three Months Ended March 31, 2019 U.S. Non-U.S. Total MIS: Corporate finance (CFG) (1) $ 242.6 $ 112.8 $ 355.4 Structured finance (SFG) (1) 62.2 38.5 100.7 Financial institutions (FIG) 46.0 69.8 115.8 Public, project and infrastructure finance (PPIF) 60.2 32.5 92.7 Total ratings revenue 411.0 253.6 664.6 MIS Other 0.2 5.3 5.5 Total MIS 411.2 258.9 670.1 MA: Research, data and analytics (RD&A) (2) 134.8 172.9 307.7 Enterprise risk solutions (ERS) (2) 48.4 73.5 121.9 Professional services (PS) 17.7 24.7 42.4 Total MA 200.9 271.1 472.0 Total MCO $ 612.1 $ 530.0 $ 1,142.1 Three Months Ended March 31, 2018 U.S. Non-U.S. Total MIS: Corporate finance (CFG) (1) $ 257.3 $ 132.3 $ 389.6 Structured finance (SFG) (1) 74.0 43.8 117.8 Financial institutions (FIG) 48.5 65.8 114.3 Public, project and infrastructure finance (PPIF) 53.4 39.8 93.2 Total ratings revenue 433.2 281.7 714.9 MIS Other 0.2 4.8 5.0 Total MIS 433.4 286.5 719.9 MA: Research, data and analytics (RD&A) (2) 112.6 154.5 267.1 Enterprise risk solutions (ERS) (2) 38.5 63.7 102.2 Professional services (PS) 13.2 24.3 37.5 Total MA 164.3 242.5 406.8 Total MCO $ 597.7 $ 529.0 $ 1,126.7 (1) Pursuant to certain organizational realignments in the first quarter of 2019, MIS now reports revenue from REITs, which was previously classified in the SFG LOB, as a component of the CFG LOB. The amounts reclassified were not material and prior year revenue by LOB has been reclassified to conform to this new presentation. (2) Pursuant to organizational/product realignments in the first quarter of 2019, revenue relating to the Bureau van Dijk FACT product, a credit assessment and origination software solution, is now reported in the ERS LOB. This revenue was previously reported in the RD&A LOB. Prior year revenue by LOB has been reclassified to conform to this new presentation, and the amounts reclassified were not material. The following table presents the Company’s reportable segment revenues disaggregated by segment and geographic region: Three Months Ended March 31, 2019 2018 MIS: U.S. $ 411.2 $ 433.4 Non-U.S. EMEA 148.5 181.1 Asia-Pacific 78.9 72.6 Americas 31.5 32.8 Total Non-U.S. 258.9 286.5 Total MIS 670.1 719.9 MA: U.S. 200.9 164.3 Non-U.S. EMEA 184.1 166.2 Asia-Pacific 53.3 47.6 Americas 33.7 28.7 Total Non-U.S. 271.1 242.5 Total MA 472.0 406.8 Total MCO $ 1,142.1 $ 1,126.7 The tables below summarize the split between transaction and relationship revenue. In the MIS segment, excluding MIS Other, transaction revenue represents the initial rating of a new debt issuance as well as other one-time fees while relationship revenue represents the recurring monitoring fees of a rated debt obligation and/or entities that issue such obligations, as well as revenue from programs such as commercial paper, medium-term notes and shelf registrations. In MIS Other, transaction revenue represe nts revenue from professional services and outsourcing engagements and relationship revenue represents subscription-based revenues. In the MA segment, relationship revenue represents subscription-based revenues and software maintenance revenue. Transaction revenue in MA represents perpetual software license fees and revenue from software implementation services, risk management advisory projects, training and certification services, and outsourced research and analytical engagements. Three Months Ended March 31, 2019 2018 Transaction Relationship Total Transaction Relationship Total Corporate Finance $ 249.5 $ 105.9 $ 355.4 $ 283.4 $ 106.2 $ 389.6 70% 30% 100% 73% 27% 100% Structured Finance $ 57.3 $ 43.4 $ 100.7 $ 74.6 $ 43.2 $ 117.8 57% 43% 100% 63% 37% 100% Financial Institutions $ 47.9 $ 67.9 $ 115.8 $ 50.0 $ 64.3 $ 114.3 41% 59% 100% 44% 56% 100% Public, Project and Infrastructure Finance $ 54.7 $ 38.0 $ 92.7 $ 54.4 $ 38.8 $ 93.2 59% 41% 100% 58% 42% 100% MIS Other $ 0.5 $ 5.0 $ 5.5 $ 0.6 $ 4.4 $ 5.0 9% 91% 100% 12% 88% 100% Total MIS $ 409.9 $ 260.2 $ 670.1 $ 463.0 $ 256.9 $ 719.9 61% 39% 100% 64% 36% 100% Moody's Analytics $ 71.5 (1) $ 400.5 $ 472.0 $ 60.8 (1) $ 346.0 $ 406.8 15% 85% 100% 15% 85% 100% Total Moody's Corporation $ 481.4 $ 660.7 $ 1,142.1 $ 523.8 $ 602.9 $ 1,126.7 42% 58% 100% 46% 54% 100% (1) Revenue from software implementation services and risk management advisory projects, while classified by management as transactional revenue, is recognized over time under the New Revenue Accounting Standard (refer to the following table). The following table presents the timing of revenue recognition: Three Months Ended March 31, 2019 MIS MA Total Revenue recognized at a point in time $ 409.9 $ 30.4 $ 440.3 Revenue recognized over time 260.2 441.6 701.8 Total $ 670.1 $ 472.0 $ 1,142.1 Three Months Ended March 31, 2018 MIS MA Total Revenue recognized at a point in time $ 463.0 $ 15.5 $ 478.5 Revenue recognized over time 256.9 391.3 648.2 Total $ 719.9 $ 406.8 $ 1,126.7 Unbilled receivables, Deferred revenue and Remaining performance obligations Unbilled receivables At March 31, 2019 and December 31, 2018 , accounts receivable included $ 364.9 million and $ 311.8 million , respectively, of unbilled receivables related to the MIS segment . Certain MIS arrangements contain contractual terms whereby the customers are billed in arrears for annual monitoring services , requiring revenue to be accrued as an unbilled receivable as such services a re provided . In addition, for certain MA arrangements, the timing of when the Company has the unconditional right to consideration and recognizes revenue occurs prior to invoicing the customer. Consequently, at March 31, 2019 and December 31, 2018, accounts receivable included $ 5 3.3 million and $ 59.5 million , respectively, of unbilled receivables related to the MA segment. Deferred revenue The Company recognizes deferred revenue when a contract requires a customer to pay consideration to the Company in advance of when revenue related to that contract is recognized. This deferred revenue is relieved when the Company satisfies the related performance obligation and revenue is recognized. Significant changes in the deferred revenue balances dur ing the t hree months ended March 31 , 201 9 are as follows: Three Months Ended March 31, 2019 MIS MA Total Balance at January 1, 2019 $ 325.4 $ 750.3 $ 1,075.7 Changes in deferred revenue Revenue recognized that was included in the deferred revenue balance at the beginning of the period (92.8) (306.7) (399.5) Increases due to amounts billable excluding amounts recognized as revenue during the period 155.2 346.7 501.9 Effect of exchange rate changes 0.5 4.6 5.1 Total changes in deferred revenue 62.9 44.6 107.5 Balance at March 31, 2019 $ 388.3 $ 794.9 $ 1,183.2 Deferred revenue - current portion $ 271.6 $ 790.7 $ 1,062.3 Deferred revenue - noncurrent portion $ 116.7 $ 4.2 $ 120.9 Significant changes in the deferred revenue balances during the three months ended March 31, 2018 are as follows: Three Months Ended March 31, 2018 MIS MA Total Balance at January 1, 2018 (after New Revenue Accounting Standard transition adjustment) $ 334.7 $ 611.6 $ 946.3 Changes in deferred revenue Revenue recognized that was included in the deferred revenue balance at the beginning of the period (93.4) (252.0) (345.4) Increases due to amounts billable excluding amounts recognized as revenue during the period 154.9 357.9 512.8 Effect of exchange rate changes 1.3 11.5 12.8 Total changes in deferred revenue 62.8 117.4 180.2 Balance at March 31, 2018 $ 397.5 $ 729.0 $ 1,126.5 Deferred revenue - current portion $ 273.4 $ 725.3 $ 998.7 Deferred revenue - noncurrent portion $ 124.1 $ 3.7 $ 127.8 The increase in d eferred revenue during both the three months ended March 31, 2019 and 2018 is primarily due to the significant portion of contract renewals that occur during the first quarter within both segments. Remaining performance obligations The following tables include the expected recognition period for the remaining performance obligations for each reportab le segment as of March 31, 2019 : MIS Total Less than 1 year 1 - 5 years 6 - 10 Years 11 - 15 years 16-20 years Over 20 Years $ 151.2 $ 23.5 $ 70.2 $ 41.5 $ 6.5 $ 4.1 $ 5.4 The balances in the MIS table above largely reflect deferred revenue related to monitoring fees for certain structured finance products, primarily CMBS , where the issuers can elect to pay the monitoring fees for the life of the security in advance. With respect to the remaining performance obligations for the MIS segment, t he Company has applied a practical expedient set forth in ASC Topic 606 permitting the omission from the table above for unsatisfied performance obligations relating to contracts with a n original expected length of one year or less. MA Total Less than 1 Year 1 - 2 Years Over 2 Years $ 2,053.3 $ 1,334.0 $ 491.0 $ 228.3 The balances in the MA table above include both amounts recorded as deferred revenue on the balance sheet as of March 31, 2019 as well as amounts not yet invoiced to customers as of March 31, 2019 largely reflecting future revenue related to signed multi-year arrangements for hosted and installed subscription based products.

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	3 Months Ended
	Mar. 31, 2019
Stock-Based Compensation [Abstract]
STOCK-BASED COMPENSATION	NOTE 4 . STOCK-BASED COMPENSATION Presented below is a summary of the stock-based compensation cost and associated tax benefit included in the accompanying consolidated statements of operations: Three Months Ended March 31, 2019 2018 Stock-based compensation expense $ 35.7 $ 35.1 Tax benefit $ 7.8 $ 7.2 During the first three months of 2019 , th e Company granted 0.2 million employee stock options, which had a weighted av erage grant date fair value of $43.10 per share based on the Black-Scholes option-pricing model. The Company also granted 0.8 million shares of restricted stock in the first three months of 2019 , which had a weighted av erage grant date fair value of $173.58 per share . Both the employee stock options and restricted stock generally vest rata bly over a four-year period. Ad ditionally, the Company granted 0.1 million shares of performance-based awards whereby the number of shares that ultimately vest are based on the achievement of certain non-market based performance metrics of the Co mpany over a three-year period. The weighted average grant date fair value of these awards was $167.82 per share. The following weighted average assumptions were used in determining the fair value for options granted in 2019 : Expected dividend yield 1.15% Expected stock volatility 23.62% Risk-free interest rate 2.60% Expected holding period 6.2 years Grant date fair value $43.10 Unrecognized stock-based compensation expense at March 31, 2019 was $11.4 million and $239.2 million for stock options and unvested restricted stock, respectively, which is expected to be recognized over a weighted average period of 2.3 years and 2.7 years, respectively. Additionally, there was $40.8 million of unrecognized stock-based compensation expense relating to the aforementioned non-market based performance-based awards, which is expected to be recognized o ver a weighted average period of 2.2 years. The following table summarize information relating to stock option exercises and restricted stock vesting: Three Months Ended March 31, 2019 2018 Exercise of stock options: Proceeds from stock option exercises $ 11.9 $ 26.6 Aggregate intrinsic value $ 35.6 $ 61.9 Tax benefit realized upon exercise $ 8.5 $ 15.0 Number of shares exercised 0.3 0.5 Vesting of restricted stock: Fair value of shares vested $ 146.5 $ 146.7 Tax benefit realized upon vesting $ 33.6 $ 33.9 Number of shares vested 0.8 0.9 Vesting of performance-based restricted stock: Fair value of shares vested $ 47.5 $ 23.0 Tax benefit realized upon vesting $ 11.5 $ 5.5 Number of shares vested 0.3 0.1

INCOME TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2019
Income Taxes [Abstract]
INCOME TAXES	NOTE 5 . INCOME TAXES Moody’s effective tax rate was 9.2% and 14.6% for the three months ended March 31, 2019 and 2018, respectively. The decrease in the ETR was primarily due to favorable IRS Regulations issued in the first quarter of 2019 and lower non-U . S . taxes on certain software development. The Company’s quarterly tax expense differs from the tax computed by applying its estimated annual effective tax rate to this quarter’s pre-tax earnings due to Excess Tax Benefits from stock compensation of $ 26.6 million and net reductions to tax positions of $ 37.3 million. The Company classifies interest related to UTPs in interest expense, net in its consolidated statements of operations. Penalties, if incurred, would be recognized in other non-operating (expense) income, n et. The Company had a decrease in its UTPs of $ 20.2 million ($ 20.2 million , net of federal tax) during the first quarter of 2019. Moody’s Corporation and subsidiaries are subject to U.S. federal income tax as well as income tax in various state, local an d foreign jurisdictions. The Company’s U.S. federal income tax returns for 2015 through 2017 remain open to examination. The Company’s New York State tax returns for 2011 through 2014 are currently under examination and the Company’s New York City tax retu rn for 2014 is currently under examination. The Company’s U.K. tax return for 2012 is currently under examination and its returns for 2013 through 2017 remain open to examination. For ongoing audits, it is possible the balance of UTPs could decrease in th e next twelve months as a result of the settlement of these audits, which might involve the payment of additional taxes, the adjustment of certain deferred taxes and/or the recognition of tax benefits. It is also possible that new issues might be raised by tax authorities which could necessitate increases to the balance of UTPs. As the Company is unable to predict the timing or outcome of these audits, it is therefore unable to estimate the amount of changes to the balance of UTPs at this time. However, the Company believes that it has adequately provided for its financial exposure relating to all open tax years by tax jurisdiction in accordance with the applicable provisions of Topic 740 of the ASC regarding UTPs. The following table shows the amount the C ompany paid for income taxes: Three Months Ended March 31, 2019 2018 Income taxes paid $ 36.9 $ 44.2

WEIGHTED AVERAGE SHARES OUTSTAN

WEIGHTED AVERAGE SHARES OUTSTANDING	3 Months Ended
	Mar. 31, 2019
Weighted Average Shares Outstanding [Abstract]
WEIGHTED AVERAGE SHARES OUTSTANDING	NOTE 6 . WEIGHTED AVERAGE SHARES OUTSTANDING Below is a reconciliation of basic to diluted shares outstanding: Three Months Ended March 31, 2019 2018 Basic 190.4 191.4 Dilutive effect of shares issuable under stock-based compensation plans 2.4 3.1 Diluted 192.8 194.5 Anti-dilutive options to purchase common shares and restricted stock as well as contingently issuable restricted stock which are excluded from the table above 0.4 0.7 The calculation of diluted EPS requires certain assumptions regarding the use of both cash proceeds and assumed proceeds that would be received upon the exercise of stock options and vesting of restricted stock outstanding as of March 31, 2019 and 2018 .

ACCELERATED SHARE REPURCHASE PR

ACCELERATED SHARE REPURCHASE PROGRAM	3 Months Ended
	Mar. 31, 2019
Accelerated Share Repurchase Program [Abstract]
ACCELERATED SHARE REPURCHASE PROGRAM	NOTE 7 . ACCELERATED SHARE REPURCHASE PROGRAM On February 20, 2019, the Company entered into an ASR agreement with a financial institution counterparty to repurchase $ 500 million of its outstanding common stock. The Company paid $500 million to the counterparty and received an initial delivery of 2.2 million shares of its common stock . Final s ettlement of the ASR agreement was comp leted on April 26, 2019 and the Company rece ived delivery of an additional 0 . 6 million shares of the Company’s common stock. In total, the Company repurchased 2. 8 million shares of the Company’s common stock during th e term of the ASR Agreement, based on the volume-weighted average price (net of discount) of $ 180.33 /share over the duration of the program. The initial share repurchase and final share settlement were recorded as a reduction to shareholders’ equity.

CASH EQUIVALENT AND INVESTMENTS

CASH EQUIVALENT AND INVESTMENTS	3 Months Ended
	Mar. 31, 2019
Cash and Cash Equivalents [Abstract]
CASH EQUIVALENT AND INVESTMENT	NOTE 8 . CASH EQUIVALENTS AND INVESTMENTS The table below provides additional information on the Company’s cash equivalents and investments: As of March 31, 2019 Balance sheet location Cost Gross Unrealized Gains Fair Value Cash and cash equivalents Short-term investments Other assets Certificates of deposit and money market deposit accounts (1) $ 551.0 $ - $ 551.0 $ 432.4 $ 110.9 $ 7.7 Open-ended mutual funds $ 15.6 $ 2.1 $ 17.7 $ - $ 3.1 $ 14.6 As of December 31, 2018 Balance sheet location Cost Gross Unrealized Gains Fair Value Cash and cash equivalents Short-term investments Other assets Money market mutual funds $ 15.2 $ - $ 15.2 $ 15.2 $ - $ - Certificates of deposit and money market deposit accounts (1) $ 1,022.4 $ - $ 1,022.4 $ 904.3 $ 115.8 $ 2.3 Open-ended mutual funds $ 29.5 $ 3.8 $ 33.3 $ - $ 16.7 $ 16.6 (1) Consists of time deposits and money market deposit accounts. The remaining contractual maturities for the certificates of deposits classified as short-term investments were one to 12 months at both March 31, 2019 and December 31, 2018. The remaining contractual maturities for the certificates of deposits classified in other assets are 13 to 32 months at March 31, 2019 and 14 to 36 months at December 31, 2018. Time deposits with a maturity of less than 90 days at time of purchase are classified as cash and cash equivalents.

ACQUISITIONS

ACQUISITIONS	3 Months Ended
	Mar. 31, 2019
Acquisitions [Abstract]
ACQUISITIONS	NOTE 9 . ACQUISITIONS Vigeo Eiris On April 12 , 201 9 , the Company acquired a majority stake in Vigeo Eiris, a global leader in Environmental, Social and Governance (ESG) research, data and assessments. The acquisition furthers Moody’s objective of promoting global standards for ESG for use by market participants . The aggregate purchase price was not material and the near term impact to the Company’s operations and cash flows is not expected to be material. Vigeo Eiris will operate in the MIS reportable segment and its revenue will be reported in the MIS Other LOB.

DERIVATIVE INSTRUMENTS AND HEDG

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	3 Months Ended
	Mar. 31, 2019
Derivative Instruments and Hedging Activities [Abstract]
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	NOTE 10 . DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES The Company is exposed to global market risks, including risks from changes in FX rates and changes in interest rates. Accordingly, the Company uses derivatives in certain instances to manage the aforementioned financial exposures that occur in the normal course of business. The Company does not hold or issue derivatives for speculative purposes. Derivatives and non-derivative instruments designated as accounting hedges: Fair Value Hedges Interest Rate Swaps The Company has entered into interest rate swaps to convert the fixed interest rate on certain of its long-term debt to a floating interest rate based on the 3-month LIBOR. The purpose of these hedges is to mitigate the risk associated with changes in the fair value of the long-term debt, thus the Company has designated these swaps as fair value hedges. The fair value of the swaps is adjusted quarterly with a corresponding adjustment to the carrying value of the debt. The changes in the fair value of the swaps and the underlying hedged item generally offset and the net cash settlements on the swaps are recorded each period within interest expense, net in the Company’s consolidated statements of operations. The following table summarizes the Com pany’s interest rate swaps designated as fair value hedges: Hedged Item Nature of Swap Notional Amount Floating Interest Rate As of March 31, 2019 As of December 31, 2018 2010 Senior Notes due 2020 Pay Floating/Receive Fixed $ 500.0 $ 500.0 3-month USD LIBOR 2012 Senior Notes due 2022 Pay Floating/Receive Fixed 330.0 330.0 3-month USD LIBOR 2017 Senior Notes due 2021 Pay Floating/Receive Fixed 500.0 500.0 3-month USD LIBOR 2017 Senior Notes due 2023 Pay Floating/Receive Fixed 250.0 - 3-month USD LIBOR Total $ 1,580.0 $ 1,330.0 Refer to Note 17 for information on the cumulative amount of fair value hedging adjustments included in the carrying amount of the above hedged items. The following table summarizes the impact to the statement of operations of the Company’s interest rate swaps designated as fair value hedges: Amount of Income (Expense) Recognized in the Statements of Operations Total amounts of financial statement line item presented in the statements of operations in which the effects of fair value hedges are recorded Three Months Ended March 31, 2019 2018 Interest expense, net $ (52.5) $ (50.7) Descriptions Location on Consolidated Statements of Operations Net interest settlements and accruals on interest rate swaps Interest expense, net $ (0.2) $ (0.1) Fair value changes on interest rate swaps Interest expense, net $ 10.8 $ (9.2) Fair value changes on hedged debt Interest expense, net $ (10.8) $ 9.2 Net investment hedges The Company has designated € 500 million of the 2015 Senior Notes Due 2027 as a net investment hedge to mitigate FX exposure related to a portion of the Company’s euro net investment in certain foreign subsidiaries against changes in euro/USD exchange rates . This hedge is designated as an accounting hedge under the applicable sections of ASC Topic 815 and will end upon the repayment of the notes in 2027, unless terminated early at the discretion of the Company. The Company has also entered into cross-currency swaps to mitigate FX exposure related to a portion of the Company’s euro net investment in certain foreign subsidiaries against changes in euro/USD exchange rates. The following table provides information on the cross-currency swaps Pay Receive Nature of Swap Notional Amount Weighted Average Interest Rate Notional Amount Weighted Average Interest Rate Pay Fixed/Receive Fixed € 663.6 1.51% $ 750.0 4.13% Pay Floating/Receive Floating 931.2 Based on 3-month EURIBOR 1,080.0 Based on 3-month USD LIBOR Total € 1,594.8 $ 1,830.0 These hedges were designated as net investment hedges under ASC Topic 815 and the purpose of these hedges is to mitigate FX exposure related to a portion of the Company’s euro net investments in certain foreign subsidiaries against changes in euro/USD exchange rates. These hedges will expire and be settled in 2021, 2022, 2023, and 2024 for € 422.5 million, € 287.7 million, € 441.9 million and € 442.6 million of the total notional amount, respectively, unless terminated early at the discretion of the Company . The following table provides information on the gains/(losses) on the Company’s net investment and cash flow hedges: Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax Gain/(Loss) Recognized in Income on Derivative (Amount Excluded from Effectiveness Testing) Derivative and Non-Derivative Instruments in Net Investment Hedging Relationships Three Months Ended March 31, Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 2019 (2) 2018 Cross currency swaps $ 15.2 $ - - - 8.3 - Long-term debt 8.3 (1) (10.9) - - - - Total net investment hedges $ 23.5 $ (10.9) $ - $ - $ 8.3 $ - Derivatives in Cash Flow Hedging Relationships Cross currency swap $ - $ 1.5 $ 0.1 $ 0.1 $ - $ - Interest rate contracts - - (0.1) - - - Total cash flow hedges $ - $ 1.5 $ - $ 0.1 $ - $ - Total $ 23.5 $ (9.4) $ - $ 0.1 $ 8.3 $ - (1) Due to the Company's adoption of ASU 2018-02 during the first quarter of 2019, $2.5 million related to the tax effect of this net investment hedge was reclassified to retained earnings. Refer to Note 1 for further details. (2) Effective with the adoption of ASU 2017-12, the Company has elected to assess the effectiveness of its net investment hedges based on changes in spot exchange rates. Accordingly, amounts recognized directly into Net Income during the first quarter of 2019 related to its cross-currency swaps represent net periodic interest settlements and accruals, which are recognized in interest expense, net. The cumulative amount of net investment hedge and cash flow hedge gains (losses) remaining in AOCI is as follows: Cumulative Gains/(Losses), net of tax March 31, December 31, 2019 2018 Net investment hedges Cross currency swaps $ 27.5 $ 12.3 FX forwards 23.5 23.5 Long-term debt 2.7 (3.1) Total net investment hedges $ 53.7 $ 32.7 Cash flow hedges Interest rate contracts $ (2.3) $ (2.4) Cross currency swap 2.4 2.5 Total cash flow hedges 0.1 0.1 Total net gain in AOCI $ 53.8 $ 32.8 Derivatives not designated as accounting hedges: Foreign exchange forwards The Company also enters into foreign exchange forwards to mitigate the change in fair value on certain assets and liabilities denominated in currencies other than a subsidiary’s functional currency. These forward contracts are not designated as accounting hedges under the applicable sections of Topic 815 of the ASC. Accordingly, changes in the fair value of these contracts are recognized immediately in other non-operating (expense ) income, net in the Company’s consolidated statements of operations along with the FX gain or loss recognized on the assets and liabilities denominated in a currency other than the subsidiary’s functional currency. These contracts have expiration dates at various times through May 2019. The following table summarizes the notional amounts of the Company’s outstanding foreign exchange forwards: March 31, December 31, 2019 2018 Notional amount of currency pair: Sell Buy Sell Buy Contracts to sell USD for GBP $ 492.5 £ 371.0 $ 310.3 £ 241.2 Contracts to sell USD for Japanese Yen $ 14.4 ¥ 1,600.0 $ 14.3 ¥ 1,600.0 Contracts to sell USD for Canadian dollars $ 87.4 C$ 115.0 $ 99.0 C$ 130.0 Contracts to sell USD for Singapore dollars $ 35.7 S$ 48.0 $ - S$ - Contracts to sell USD for Euros $ 68.6 € 60.0 $ 212.8 € 184.6 NOTE: € = Euro, £ = British pound, $ = U.S. dollar, ¥ = Japanese Yen, C$ = Canadian dollar, S$= Singapore dollars The following table summarizes the impact to the consolidated statements of oper ations relating to the net gain/ (loss) on the Company’s derivatives which are not designated as hedging instruments: Three Months Ended March 31, Derivatives Not Designated as Accounting Hedges Location on Statements of Operations 2019 2018 Foreign exchange forwards Other non-operating (expense) income, net $ 1.4 $ (52.3) The table below shows the classification between assets and liabilities on the Company’s consolidated balance sheets for the fair value of the derivative instrument as well as the carrying value of its non-derivative debt instruments designated and qualifying as net investment hedges : Derivative and Non-Derivative Instruments Balance Sheet Location March 31, 2019 December 31, 2018 Assets: Derivatives designated as accounting hedges: Cross-currency swaps designated as net investment hedges Other assets $ 36.7 $ 19.4 Interest rate swaps designated as fair value hedges Other assets 15.3 7.5 Total derivatives designated as accounting hedges 52.0 26.9 Derivatives not designated as accounting hedges: FX forwards on certain assets and liabilities Other current assets 0.3 1.4 Total assets $ 52.3 $ 28.3 Liabilities: Derivatives designated as accounting hedges: Cross-currency swaps designated as net investment hedges Other liabilities - 2.9 Interest rate swaps designated as fair value hedges Other liabilities 2.3 5.3 Total derivatives designated as accounting hedges 2.3 8.2 Non-derivative instrument designated as accounting hedge Long-term debt designated as net investment hedge Long-term debt 561.4 571.6 Derivatives not designated as accounting hedges: FX forwards on certain assets and liabilities Accounts payable and accrued liabilities 10.9 8.2 Total liabilities $ 574.6 $ 588.0

GOODWILL AND OTHER ACQUIRED INT

GOODWILL AND OTHER ACQUIRED INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2019
Goodwill And Other Acquired Intangible Assets [Abstract]
GOODWILL AND OTHER ACQUIRED INTANGIBLE ASSETS	NOTE 11 . GOODWILL AND OTHER ACQUIRED INTANGIBLE ASSETS The following table summarizes the activity in goodwill for the periods indicated: Three Months Ended March 31, 2019 MIS MA Consolidated Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Balance at beginning of year $ 257.8 $ - $ 257.8 $ 3,535.7 $ (12.2) $ 3,523.5 $ 3,793.5 $ (12.2) $ 3,781.3 Foreign currency translation adjustments 9.4 - 9.4 (28.2) - (28.2) (18.8) - (18.8) Ending balance $ 267.2 $ - $ 267.2 $ 3,507.5 $ (12.2) $ 3,495.3 $ 3,774.7 $ (12.2) $ 3,762.5 Year ended December 31, 2018 MIS MA Consolidated Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Balance at beginning of year $ 285.2 $ - $ 285.2 $ 3,480.2 $ (12.2) $ 3,468.0 $ 3,765.4 $ (12.2) $ 3,753.2 Additions/ adjustments - - - 211.5 - 211.5 211.5 - 211.5 Foreign currency translation adjustments (27.4) - (27.4) (156.0) - (156.0) (183.4) - (183.4) Ending balance $ 257.8 $ - $ 257.8 $ 3,535.7 $ (12.2) $ 3,523.5 $ 3,793.5 $ (12.2) $ 3,781.3 The 2018 additions/adjustments for the MA segment in the table above primarily relate to the acquisitions of Reis and Omega Performance. Acquired intangible assets and related amortization consisted of: March 31, December 31, 2019 2018 Customer relationships $ 1,360.7 $ 1,367.5 Accumulated amortization (230.2) (214.2) Net customer relationships 1,130.5 1,153.3 Trade secrets 29.9 29.8 Accumulated amortization (28.3) (28.2) Net trade secrets 1.6 1.6 Software/product technology 349.2 353.3 Accumulated amortization (107.7) (101.8) Net software/product technology 241.5 251.5 Trade names 155.9 155.1 Accumulated amortization (36.5) (34.1) Net trade names 119.4 121.0 Other (1) 70.8 70.4 Accumulated amortization (33.4) (31.7) Net other 37.4 38.7 Total acquired intangible assets, net $ 1,530.4 $ 1,566.1 (1) Other intangible assets primarily consist of databases, covenants not to compete, and acquired ratings methodologies and models. Amortization expense relating to acquired intangible assets is as follows: Three Months Ended March 31, 2019 2018 Amortization expense $ 26.4 $ 25.7 Estimated future amortization expense for acquired intangible assets subject to amortization is as follows: Year Ending December 31, 2019 (after March 31) $ 71.0 2020 100.5 2021 100.3 2022 100.3 2023 97.3 Thereafter 1,061.0 Total estimated future amortization $ 1,530.4

RESTRUCTURING

RESTRUCTURING	3 Months Ended
	Mar. 31, 2019
Restructuring [Abstract]
RESTRUCTURING	NOTE 12 RESTRUCTURING On October 26, 2018, the chief executive officer of Moody’s approved a restructuring program (the “2018 Restructuring Program”) that the Company estimates will result in annualized savings of approximately $ 40 to $ 50 million per year, a portion of which will benefit 2019. The 2018 Restructuring Program is estimated to result in total pre-tax charges of $ 70 to $ 80 mil lion. The Program is expected to be substantially completed by June 30, 2019. The 2018 Restructuring Program include s relocation of certain functions from high-cost to lower-cost jurisdictions, a reduction of staff, including from recent acquisitions and pursuant to a review of the business criticality of certain positions, and the rationalization and exit of certain re al estate leases due to consolidation of various business activities. The exit from certain leased office space began in the fourth quarter of 2018 and will entail approximately $ 35 to $ 40 million of the charges to either terminate or sublease the affected real estate leases. The 2018 Restructuring Program is also anticipated to represent approximately $ 35 to $ 40 million of personnel-related restructuring charges, an amount that includes severance and related costs primarily determined under the Company’s e xisting severance plans. Cash outlays associated with the employee termination cost component of the 2018 Restructuring Program are anticipated to be approximately $ 35 to $ 40 million, the majority of which will be paid in 2019. Total expenses included in t he accompanying consolidated statements of operations relating to the 2018 Restructuring Program are as follows: Three Months Ended March 31, 2019 2018 2018 Restructuring Program $ 5.5 $ - Changes to the restructuring liability during the first three months of 201 9 were as follows : Employee Termination Costs Contract Termination Costs Total Restructuring Liability Balance as of December 31, 2018 $ 29.9 $ 12.4 $ 42.3 2018 Restructuring Program: Adoption of New Lease Accounting Standard - (10.9) (1) (10.9) (1) Cost incurred and adjustments 1.8 2.2 (2) 4.0 (2) Cash payments and adjustments (5.9) (0.7) (6.6) Balance as of March 31, 2019 $ 25.8 $ 3.0 $ 28.8 2018 Restructuring Program: Cumulative expense incurred to date $ 34.6 $ 19.6 (1) Upon the adoption of the New Lease Accounting Standard, the Company recorded a reclassification of $10.9 million of liabilities for costs associated with certain real estate leases which were exited in previous years, as a reduction of the ROU Asset capitalized upon adoption. (2) Excludes $1.5 million of non-cash acceleration of amortization of leasehold improvements relating to the rationalization and exit of certain real estate leases. As of March 31, 2019 , the majority of the remaining $28.8 million restructuring liability is expected to be paid out during the next 12 months.

FAIR VALUE

FAIR VALUE	3 Months Ended
	Mar. 31, 2019
Fair Value [Abstract]
FAIR VALUE	NOTE 13 . FAIR VALUE The table below presents information about items that are carried at fair value at March 31, 2019 and December 31, 2018 : Fair Value Measurement as of March 31, 2019 Description Balance Level 1 Level 2 Assets: Derivatives (1) $ 52.3 $ - $ 52.3 Mutual funds 17.7 17.7 - Total $ 70.0 $ 17.7 $ 52.3 Liabilities: Derivatives (1) $ 13.2 $ - $ 13.2 Total $ 13.2 $ - $ 13.2 Fair Value Measurement as of December 31, 2018 Description Balance Level 1 Level 2 Assets: Derivatives (1) $ 28.3 $ - $ 28.3 Money market mutual funds 15.2 15.2 - Mutual funds 33.3 33.3 - Total $ 76.8 $ 48.5 $ 28.3 Liabilities: Derivatives (1) $ 16.4 $ - $ 16.4 Total $ 16.4 $ - $ 16.4 (1) Represents FX forwards on certain assets and liabilities as well as interest rate swaps and cross-currency swaps as more fully described in Note 10 to the condensed consolidated financial statements. The following are descriptions of the methodologies utilized by the Company to estimate the fair value of its derivative contracts, fixed maturity plans, and money market mutual funds: Derivatives: In determining the fair value of the derivative contracts in the table above, the Company utilizes industry standard valuation models. Where applicable, these models project future cash flows and discount the future amounts to a present value using spot rates, forward points, currency volatilities, inte rest rates as well as the risk of non-performance of the Company and the counterparties with whom it has derivative contracts. The Company established strict counterparty credit guidelines and only enters into transactions with financial institutions that adhere to these guidelines. Accordingly, the risk of counterparty default is deemed to be minimal. Mutual funds and money market mutual funds: T he mutual f unds in the table above are deemed to be equity securities with readily determinable fair values with chang es in the fair value recognized through net income under ASC Topic 321. The fair value of these instruments is determined using Level 1 inputs as defined in the ASC.

OTHER BALANCE SHEET AND STATEME

OTHER BALANCE SHEET AND STATEMENT OF OPERATIONS INFORMATION	3 Months Ended
	Mar. 31, 2019
Other Balance Sheet And Statement Of Operations Information [Abstract]
OTHER BALANCE SHEET AND STATEMENT OF OPERATIONS INFORMATION	NOTE 14 OTHER BALANCE SHEET AND STATEMENT OF OPERATIONS INFORMATION The following tables contain additional detail related to certain balance sheet captions: March 31, December 31, 2019 2018 Other current assets: Prepaid taxes $ 103.8 $ 100.1 Prepaid expenses 104.4 102.0 Capitalized costs to obtain and fulfill sales contracts 76.4 77.2 Other 2.0 3.0 Total other current assets $ 286.6 $ 282.3 March 31, December 31, 2019 2018 Other assets: Investments in non-consolidated affiliates $ 111.6 $ 104.6 Deposits for real-estate leases 13.7 13.5 Indemnification assets related to acquisitions 16.2 16.1 Mutual funds and fixed deposits 22.3 18.9 Costs to obtain sales contracts 86.1 78.0 Other 71.3 43.2 Total other assets $ 321.2 $ 274.3 March 31, December 31, 2019 2018 Accounts payable and accrued liabilities: Salaries and benefits $ 132.3 $ 112.5 Incentive compensation 51.0 154.5 Customer credits, advanced payments and advanced billings 22.9 20.4 Self-insurance reserves 9.3 10.6 Dividends 4.0 6.5 Professional service fees 58.1 47.7 Interest accrued on debt 36.4 70.5 Accounts payable 19.5 30.1 Income taxes 65.4 71.4 Pension and other retirement employee benefits 6.4 6.4 Accrued royalties 14.0 25.1 Foreign exchange forwards on certain assets and liabilities 10.9 8.2 Restructuring liability 25.6 35.5 Other 81.3 95.8 Total accounts payable and accrued liabilities $ 537.1 $ 695.2 March 31, December 31, 2019 2018 Other liabilities: Pension and other retirement employee benefits $ 256.5 $ 249.2 Deferred rent - non-current portion (1) - 94.3 Interest accrued on UTPs 74.9 69.6 Other tax matters 1.3 1.3 Income tax liability - non-current portion (2) 125.3 125.3 Interest rate swaps 2.3 5.3 Restructuring liability 3.2 6.8 Other 23.1 24.7 Total other liabilities $ 486.6 $ 576.5 (1) Pursuant to the adoption of the New Lease Accounting Standard, deferred rent relating to operating leases was reclassified to operating lease ROU Asset. (2) Primarily reflects the transition tax pursuant to the Tax Act, which was enacted into law in December 2018. Other Non-Operating Income (Expense): The following table summarizes the components of other non-operating income (expense): Three Months Ended March 31, 2019 2018 FX loss $ (6.2) $ (5.9) Net periodic pension costs - other component 4.5 2.3 Income from investments in non-consolidated affiliates 1.2 1.3 Other 2.8 3.3 Total $ 2.3 $ 1.0

COMPREHENSIVE INCOME AND ACCUMU

COMPREHENSIVE INCOME AND ACCUMULATED OTHER COMPREHENSIVE INCOME	3 Months Ended
	Mar. 31, 2019
Comprehensive Income And Accumulated Other Comprehensive Income [Abstract]
COMPREHENSIVE INCOME AND ACCUMULATED OTHER COMPREHENSIVE INCOME	NOTE 15 . COMPREHENSIVE INCOME AND ACCUMULATED OTHER COMPREHENSIVE INCOME The following table provides details about the reclassifications out of AOCI: Three Months Ended March 31, Location in the consolidated statements of operations 2019 2018 Gains (losses) on cash flow hedges Cross-currency swap $ (0.1) $ 0.1 Other non-operating income (expense), net Interest rate contract 0.1 - Interest expense, net Total before income taxes - 0.1 Income tax effect of item above - - Provision for income taxes Total net gains (losses) on cash flow hedges - 0.1 Pension and other retirement benefits Amortization of actuarial losses and prior service costs included in net income (0.5) (0.9) Operating expense Amortization of actuarial losses and prior service costs included in net income (0.3) (0.5) SG&A expense Total before income taxes (0.8) (1.4) Income tax effect of item above 0.2 0.4 Provision for income taxes Total pension and other retirement benefits (0.6) (1.0) Total (losses) gains included in Net Income attributable to reclassifications out of AOCI $ (0.6) $ (0.9) The following table shows changes in AOCI by component (net of tax): Three Months Ended March 31, 2019 Pension and Other Retirement Benefits Gains / (Losses) on Cash Flow Hedges Foreign Currency Translation Adjustments Net Gains / (Losses) on Net Investment Hedges Gains on Available for Sale Securities Total Balance December 31, 2018 $ (53.1) $ 0.1 $ (406.0) $ 32.7 $ - $ (426.3) Other comprehensive income/(loss) before reclassifications 0.8 - (34.3) 23.5 - (10.0) Amounts reclassified from AOCI 0.6 - - - - 0.6 Adoption of ASU 2018-02 (See Note 1) (17.3) - - (2.5) - (19.8) Other comprehensive income/(loss) (15.9) - (34.3) 21.0 - (29.2) Balance March 31, 2019 $ (69.0) $ 0.1 $ (440.3) $ 53.7 $ - $ (455.5) Three Months Ended March 31, 2018 Pension and Other Retirement Benefits Gains / (Losses) on Cash Flow Hedges Foreign Currency Translation Adjustments Net Losses on Net Investment Hedges Gains on Available for Sale Securities Total Balance December 31, 2017 $ (61.5) $ 0.9 $ (112.6) $ (1.3) $ 2.3 $ (172.2) Adoption of ASU 2016-01 relating to financial instruments - - - - (2.3) (2.3) Other comprehensive income/(loss) before reclassifications - 1.5 131.1 (10.9) - 121.7 Amounts reclassified from AOCI 1.0 (0.1) - - - 0.9 Other comprehensive income/(loss) 1.0 1.4 131.1 (10.9) (2.3) 120.3 Balance March 31, 2018 $ (60.5) $ 2.3 $ 18.5 $ (12.2) $ - $ (51.9)

PENSION AND OTHER POST-RETIREME

PENSION AND OTHER POST-RETIREMENT BENEFITS	3 Months Ended
	Mar. 31, 2019
Pension And Other Retirement Benefits [Abstract]
PENSION AND OTHER RETIREMENT BENEFITS	NOTE 16 . PENSION AND OTHER RETIREMENT BENEFITS M oody’s maintains funded and unfunded noncontributory Defined Benefit Pension Plans. The U.S. plans provide defined benefits using a cash balance formula based on years of service and career average salary for its employees or final average pay for selected executives. The Company also provides certain healthcare and life insurance benefits for retired U.S. employees. The retirement healthcare plans are contributory; the life insurance plans are noncontribu tory. Moody’s funded and unfunded U.S. pension plans, the U.S. retirement healthcare plans and the U.S. retirement life insurance plans are collectively referred to herein as the “Retirement Plans”. The U.S. retirement healthcare plans and the U.S. retirem ent life insurance plans are collectively referred to herein as the “Other Retirement Plans”. The non-U.S. defined benefit pension plan are immaterial. Effective January 1, 2008, the Company no longer offers DBPPs to U.S. employees hired or rehired on or a fter January 1, 2008. New U.S. employees will instead receive a retirement contribution of similar benefit value under the Company’s Profit Participation Plan. Current participants of the Company’s DBPPs continue to accrue benefits based on existing plan f ormulas. The components of net periodic benefit expense related to the Retirement Plans are as follows: Three Months Ended March 31, Pension Plans Other Retirement Plans 2019 2018 2019 2018 Components of net periodic expense Service cost $ 4.3 $ 4.8 $ 0.7 $ 0.7 Interest cost 5.1 4.4 0.3 0.3 Expected return on plan assets (5.0) (3.8) - - Amortization of net actuarial loss from earlier periods 0.9 1.6 - - Amortization of net prior service costs from earlier periods (0.1) (0.1) (0.1) (0.1) Net periodic expense $ 5.2 $ 6.9 $ 0.9 $ 0.9

INDEBTEDNESS

INDEBTEDNESS	3 Months Ended
	Mar. 31, 2019
Indebtedness [Abstract]
INDEBTEDNESS	NOTE 17 . INDEBTEDNESS The Company’s debt is recorded at its carrying amount, which represents the issuance amount plus or minus any issuance premium or discount, except for the 2010 Senior Notes, the 2012 Senior Notes, the 2017 Senior Notes due 2021 and the 2017 Senior Notes due 2023 , which are recorded at the carrying amount adjusted for the fair value of an interest rate swap used to hedge the fair value of the note. The following table summarizes t otal indebtedness: March 31, 2019 Principal Amount Fair Value of Interest Rate Swaps (1) Unamortized (Discount) Premium Unamortized Debt Issuance Costs Carrying Value Notes Payable: 5.50% 2010 Senior Notes, due 2020 $ 500.0 $ (1.5) $ (0.5) $ (0.6) $ 497.4 4.50% 2012 Senior Notes, due 2022 500.0 4.8 (1.5) (1.3) 502.0 4.875% 2013 Senior Notes, due 2024 500.0 - (1.5) (1.9) 496.6 5.25% 2014 Senior Notes (30-Year), due 2044 600.0 - 3.2 (5.4) 597.8 1.75% 2015 Senior Notes, due 2027 561.4 - - (2.9) 558.5 2.75% 2017 Senior Notes, due 2021 500.0 6.9 (0.9) (2.2) 503.8 2.625% 2017 Senior Notes, due 2023 500.0 2.8 (0.8) (2.8) 499.2 3.25% 2017 Senior Notes, due 2028 500.0 - (4.6) (3.6) 491.8 3.25% 2018 Senior Notes, due 2021 300.0 - (0.3) (1.3) 298.4 4.25% 2018 Senior Notes, due 2029 400.0 - (2.9) (3.2) 393.9 4.875% 2018 Senior Notes, due 2048 400.0 - (6.7) (4.1) 389.2 Commercial Paper 320.0 - (1.2) - 318.8 Total debt $ 5,581.4 $ 13.0 $ (17.7) $ (29.3) $ 5,547.4 Current portion (318.8) Total long-term debt $ 5,228.6 December 31, 2018 Principal Amount Fair Value of Interest Rate Swaps (1) Unamortized (Discount) Premium Unamortized Debt Issuance Costs Carrying Value Notes Payable: 5.50% 2010 Senior Notes, due 2020 $ 500.0 $ (3.7) $ (0.6) $ (0.7) $ 495.0 4.50% 2012 Senior Notes, due 2022 500.0 1.9 (1.6) (1.4) 498.9 4.875% 2013 Senior Notes, due 2024 500.0 - (1.5) (2.0) 496.5 2.75% 2014 Senior Notes (5-Year), due 2019 450.0 - (0.1) - 449.9 5.25% 2014 Senior Notes (30-Year), due 2044 600.0 - 3.2 (5.5) 597.7 1.75% 2015 Senior Notes, due 2027 571.6 - - (3.1) 568.5 2.75% 2017 Senior Notes, due 2021 500.0 4.0 (1.0) (2.4) 500.6 2.625% 2017 Senior Notes, due 2023 500.0 - (0.9) (2.8) 496.3 3.25% 2017 Senior Notes, due 2028 500.0 - (4.7) (3.7) 491.6 3.25% 2017 Senior Notes, due 2021 300.0 - (0.4) (1.5) 298.1 4.25% 2018 Senior Notes, due 2029 400.0 - (3.0) (3.3) 393.7 4.875% 2018 Senior Notes, due 2048 400.0 - (6.7) (4.1) 389.2 Total debt $ 5,721.6 $ 2.2 $ (17.3) $ (30.5) $ 5,676.0 Current portion (449.9) Total long-term debt $ 5,226.1 (1) The Company has entered into interest rate swaps on the 2010 Senior Notes, the 2012 Senior Notes, the 2017 Senior Notes due 2021 and the 2017 Senior Notes due 2023 which are more fully discussed in Note 10 above. These amounts represent the cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged debt. Commercial Paper As of March 31, 2019, the Company has CP borrowings outstanding of $ 318.8 million with a weighted average maturity date at the time of issuance of 79 days. At March 31, 2019, the weighted average remaining maturity and interest rate on CP outstanding was 44 days and 3.03 % respectively. At March 31, 2019, the Company was in compliance with all covenants contained within all of the debt agreements. All the debt agreements contain cross default provisions which state that default under one of the aforementioned debt instruments could in turn permit lenders under other debt instruments to declare borrowings outstanding under those instruments to be immedia tely due and payable. As of March 31, 2019, there were no such cross defaults. Notes Payable On January 3, 2019, the Company fully repaid $ 450 million of the 2014 Senior Notes (5-year). The repayment schedule for the Company’s borrowings is as follows: Year Ending December 31, 2010 Senior Notes due 2020 2012 Senior Notes due 2022 2013 Senior Notes due 2024 2014 Senior Notes (30-year) due 2044 2015 Senior Notes due 2027 2017 Senior Notes due 2021 2017 Senior Notes due 2023 2017 Senior Notes due 2028 2018 Senior Notes due 2021 2018 Senior Notes due 2029 2018 Senior Notes due 2048 Commercial Paper Total 2019 (After March 31) $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 320.0 $ 320.0 2020 500.0 - - - - - - - - - - - 500.0 2021 - - - - - 500.0 - - 300.0 - - - 800.0 2022 - 500.0 - - - - - - - - - - 500.0 2023 - - - - - - 500.0 - - - - - 500.0 Thereafter - - 500.0 600.0 561.4 - - 500.0 - 400.0 400.0 - 2,961.4 Total $ 500.0 $ 500.0 $ 500.0 $ 600.0 $ 561.4 $ 500.0 $ 500.0 $ 500.0 $ 300.0 $ 400.0 $ 400.0 $ 320.0 $ 5,581.4 Interest expense, net The following table summarizes the components of interest as presented in the consolidated statements of operations: Three Months Ended March 31, 2019 2018 Income $ 5.0 $ 3.2 Expense on borrowings (46.6) (51.3) UTPs and other tax related liabilities (5.6) 1.8 Net periodic pension costs - interest component (5.6) (4.7) Capitalized 0.3 0.3 Total $ (52.5) $ (50.7) The following table shows the cash paid for interest: Three Months Ended March 31, 2019 2018 Interest paid $ 72.8 $ 80.5 The fair value and carrying value of the Company’s debt (excluding c ommercial p aper) as of March 31, 2019 and December 31, 2018 are as follows : March 31, 2019 December 31, 2018 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value 5.50% 2010 Senior Notes, due 2020 $ 497.4 $ 519.2 $ 495.0 $ 517.7 4.50% 2012 Senior Notes, due 2022 502.0 526.0 498.9 513.7 4.875% 2013 Senior Notes, due 2024 496.6 537.3 496.5 522.4 2.75% 2014 Senior Notes (5-Year), due 2019 - - 449.9 449.9 5.25% 2014 Senior Notes (30-Year), due 2044 597.8 676.5 597.7 638.1 1.75% 2015 Senior Notes, due 2027 558.5 592.3 568.5 585.3 2.75% 2017 Senior Notes, due 2021 503.8 499.6 500.6 489.7 2.625% 2017 Senior Notes, due 2023 499.2 492.3 496.3 476.9 3.25% 2017 Senior Notes, due 2028 491.8 489.1 491.6 472.8 3.25% 2018 Senior Notes, due 2021 298.4 302.6 298.1 298.6 4.25% 2018 Senior Notes, due 2029 393.9 420.0 393.7 407.6 4.875% 2018 Senior Notes, due 2048 389.2 435.4 389.2 409.8 Total $ 5,228.6 $ 5,490.3 $ 5,676.0 $ 5,782.5 The fair value of the Company’s long-term debt is estimated based on quoted market prices for similar instruments. Accordingly, the inputs used to estimate the fair value of the Company’s long-term debt are classified as Level 2 inputs within the fair value hierarchy.

LEASES

LEASES	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
LEASES	NOTE 18 . LEASE S T he Company has operating leases, substantially all of which relate to the lease of office space. The Company’s leases which are classified as finance leases are not material to the condensed consolidated financial statements. Certain of the Company’s leases include options to renew, with renewal terms that can extend the lease term from one to 20 years at the Company’s discretion. The following table pre sents the components of the Company’s lease cost: Three Months Ended March 31, 2019 Operating lease cost $ 24.6 Short-term lease cost 0.4 Variable least cost 3.6 Total lease cost $ 28.6 The following tables present other information related to the Company’s operating leases: Three Months Ended March 31, 2019 Cash paid for amounts included in the measurement of operating lease liabilities $ 26.2 Right-of-use assets obtained in exchange for new operating lease liabilities $ 9.0 March 31, 2019 Weighted-average remaining lease term 7.3 years Weighted-average discount rate applied to operating leases 3.6% The following table presents a maturity analysis of the future minimum lease payments included within the Company’s operating lease liabilities at March 31, 2019: Year Ending December 31, Operating Leases 2019 (After March 31) $ 80.7 2020 104.8 2021 98.2 2022 85.1 2023 80.6 After 2023 245.1 Total lease payments (undiscounted) 694.5 Less: Interest 83.6 Present value of lease liabilities: $ 610.9 Lease liabilities - current $ 87.4 Lease liabilities - noncurrent $ 523.5

CONTINGENCIES

CONTINGENCIES	3 Months Ended
	Mar. 31, 2019
Contingencies [Abstract]
CONTINGENCIES	NOTE 19 . CONTINGENCIES Given the nature of their activities, Moody’s and its subsidiaries are subject to legal and tax proceedings, governmental, regulatory and legislative investigations, subpoenas and other inquiries, and claims and litigation by governmental and private parties that are based on ratings assigned by MIS or that are otherwise incidental to the Company’s business. Moody’s and MIS also are subject to periodic reviews, inspections, examinations and investigations by regulators in the U.S. and other jurisdictio ns, any of which may result in claims, legal proceedings, assessments, fines, penalties or restrictions on business activities. Moody’s also is subject to ongoing tax audits as addressed in N ote 5 to the financial statements. In May 2013, the Compan y and five subsidiaries (collectively, the “Company Defendants”) were served with a qui tam complaint filed by a former employee (“Plaintiff”) in New York Supreme Court (the “Court”) on behalf of New York State (the “State”) and New York City (the “City”) asserting purported claims under the New York False Claims Act (“NYFCA”). Both the State and the City were given an opportunity to intervene as plaintiffs in the action but declined to do so. In August 2013, Plaintiff filed an Amended Complaint adding Mars h & McLennan Companies, Inc. as a defendant. Plaintiff’s central allegation against the Company Defendants is that their treatment of the Company’s wholly-owned captive insurance subsidiary, Moody’s Assurance Company, Inc. (“MAC”), in their State and City tax filings between 2002 and 2014 was contrary to the State and City tax codes. Plaintiff also asserts a cause of action for retaliation under the NYFCA and alleges that his employment was improperly terminated after he reported his concerns regarding MAC’ s tax treatment internally. Plaintiff alleges that the Company underpaid State and City taxes by more than $ 120 million (which the Company believes is unsupported as a matter of fact and law), and requests statutory damages of triple that amount, as well a s unspecified damages related to the retaliation claim. In December 2016, the Court issued a decision largely denying the Company Defendants’ motion to dismiss. The Company Defendants appealed, and in August 2018, the Appellate Division of the New York Sup reme Court upheld the Court’s decision. Discovery is ongoing and, absent earlier disposition, the Company expects the case to go to trial no earlier than late 2019. The Company is unable to estimate a range of loss, and is contesting Plaintiff’s claims, wh ich it believes are meritless. Management periodically assesses the Company’s liabilities and contingencies in connection with these matters based upon the latest information available. For claims, litigation and proceedings and governmental investigation s and inquiries not related to income taxes, the Company records liabilities in the consolidated financial statements when it is both probable that a liability has been incurred and the amount of loss can be reasonably estimated and periodically adjusts th ese as appropriate. When the reasonable estimate of the loss is within a range of amounts, the minimum amount of the range is accrued unless some higher amount within the range is a better estimate than another amount within the range. In instances when a loss is reasonably possible but uncertainties exist related to the probable outcome and/or the amount or range of loss, management does not record a liability but discloses the contingency if material. As additional information becomes available, the Compa ny adjusts its assessments and estimates of such matters accordingly. Moody’s also discloses material pending legal proceedings pursuant to SEC rules and other pending matters as it may determine to be appropriate. In view of the inherent difficulty of as sessing the potential outcome of legal proceedings, governmental, regulatory and legislative investigations and inquiries, claims and litigation and similar matters and contingencies, particularly when the claimants seek large or indeterminate damages or a ssert novel legal theories or the matters involve a large number of parties, the Company often cannot predict what the eventual outcome of the pending matters will be or the timing of any resolution of such matters. The Company also may be unable to predic t the impact (if any) that any such matters may have on how its business is conducted, on its competitive position or on its financial position, results of operations or cash flows. As the process to resolve any pending matters progresses, management will continue to review the latest information available and assess its ability to predict the outcome of such matters and the effects, if any, on its operations and financial condition and to accrue for and disclose such matters as and when required. However, because such matters are inherently unpredictable and unfavorable developments or resolutions can occur, the ultimate outcome of such matters, including the amount of any loss, may differ from those estimates.

SEGMENT INFORMATION

SEGMENT INFORMATION	3 Months Ended
	Mar. 31, 2019
Segment Information [Abstract]
SEGMENT INFORMATION	NOTE 20 . SEGMENT INFORMATION The Company is organized into two operating segments: MIS and MA and accordingly, the Company reports in two reportable segments: MIS and MA. The MIS segment consists of five LOBs. The CFG, SFG, FIG and PPIF LOBs generate revenue principally from fees for the assignment and ongoing monitoring of credit ratings on debt obligations and the entities that issue such obligations in markets worldwide. The MIS Other LOB primarily consists of financial instruments pricing services in the Asia-Pacific region as well as ICRA non-ratings revenue. The MA segment develops a wide range of products and services that support the risk management activities of institutional participants in global financial markets. The MA segment con sists of three LOBs - RD&A, ERS and PS. Revenue for MIS and expenses for MA include an intersegment royalty charged to MA for the rights to use and distribute content, data and products developed by MIS. The royalty rate charged by MIS approximates the fai r value of the aforementioned content, data and products and is generally based on comparable market transactions. Also, revenue for MA and expenses for MIS include an intersegment fee charged to MIS from MA for certain MA products and services utilized in MIS’s ratings process. These fees charged by MA are generally equal to the costs incurred by MA to produ ce these products and services. Overhead expenses include costs such as rent and occupancy, information technology and support staff such as finance, h uman resources and legal. Such costs and corporate expenses that exclusively benefit one segment are fully charged to that segment. For overhead and corporate expenses that benefit both segments, in years prior to 2019, the Company generally allocated cost s ratably based on each segment’s share of total revenue. Beginning in 2019, the Company refined its methodology such that costs allocated to each segment based on the segment’s share of 2018 actual revenue comprise a “Baseline P ool” that will remain fixed over time. In subsequent periods, incremental overhead costs (or reductions thereof) will be allocated to each segment based on the prevailing shares of total revenue represented by each segment. The Company believes that this allocation method will bette r align the amount of overhead costs consumed by each segment and contribute stability to each segment’s costs over time. The impact of this refined methodology would not have resulted in a material change to previously reported segment results . “Eliminat ions” in the following table represent intersegment revenue/expense. Moody’s does not report the Company’s assets by reportable segment, as this metric is not used by the chief operating decision maker to allocate resources to the segments. Consequently, it is not practical to show assets by reportable segment. Financial Information by Segment The table below shows revenue, Adjusted Operating Income and operating income by reportable segment. Adjusted Operating Income is a financial metric utilized by the Company’s chief operating decision maker to assess the profitability of each reportable segment. Refer to Note 3 for further details on the components of the Company’s revenue Three Months Ended March 31, 2019 2018 MIS MA Eliminations Consolidated MIS MA Eliminations Consolidated Revenue $ 702.4 $ 474.4 $ (34.7) $ 1,142.1 $ 749.7 $ 411.8 $ (34.8) $ 1,126.7 Operating, SG&A 316.8 341.1 (34.7) 623.2 310.4 310.4 (34.8) 586.0 Adjusted Operating Income 385.6 133.3 - 518.9 439.3 101.4 - 540.7 Less: Restructuring 2.7 2.8 - 5.5 Depreciation and amortization 17.0 33.3 - 50.3 16.8 32.3 - 49.1 Acquisition-Related Expenses - 1.4 - 1.4 - 0.8 - 0.8 Operating income $ 365.9 $ 95.8 $ - $ 461.7 $ 422.5 $ 68.3 $ - $ 490.8 The cumulativ e restructuring charges related to the 2018 Restructuring Program, as more fully discussed in N ote 12 , for the MIS and MA reportable segments are $ 34.9 million and $ 19.3 million, respectively. The total costs expected to be incurred related to the 2018 Restructuring Program for MIS and MA are approximately $ 43 million to $ 4 8 million and $ 27 million to $ 32 million, respectively. Consolidated Revenue Information by Geographic Area Three Months Ended March 31, 2019 2018 Revenue: U.S. $ 612.1 $ 597.7 Non-U.S.: EMEA 332.6 347.3 Asia-Pacific 132.2 120.2 Americas 65.2 61.5 Total Non-U.S. 530.0 529.0 Total $ 1,142.1 $ 1,126.7

RECENTLY ISSUED ACCOUNTING STAN

RECENTLY ISSUED ACCOUNTING STANDARDS	3 Months Ended
	Mar. 31, 2019
Recently Issued Accounting Standards [Abstract]
RECENTLY ISSUED ACCOUNTING STANDARDS	NOTE 21 . RECENTLY ISSUED ACCOUNTING STANDARDS In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments”. The amendments in this ASU require the use of an “expected credit loss” impairment model for most financial assets reported at amortized cost, which will require entities to estimate expected credit losses over the lifetime of the instrument. This may result in the earlier recognition of allowances for losses. For available-for-sale debt securities wit h unrealized losses, an allowance for credit losses will be recognized as a contra account to the amortized cost carrying value of the asset rather than a direct reduction to the carrying value, with changes in the allowance impacting earnings. In November 2018, the FASB issued ASU No. 2018-19 “Codification Improvements to Topic 326, Financial Instruments—Credit Losses,” which clarifies that receivables arising from operating leases are not within the scope of Subtopic 326-20, but instead should be accounte d for in accordance with Topic 842, Leases. ASU No. 2016-13 is effective for annual and interim reporting periods beginning after December 15, 2019, with early adoption permitted in annual and interim reporting periods beginning after December 15, 2018. E ntities will apply the standard’s provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first effective reporting period. The Company is currently evaluating the impact of this ASU on its financial statements. Current ly, the Company believes that the most notable impact of this ASU will relate to its processes around the assessment of the adequacy of its allowance for doubtful accounts on accounts receivable. In June 2018, the FASB issued ASU No. 2018-07, “Compensation —Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting”, which simplifies the accounting for nonemployee share-based payment transactions. The amendments specify that ASC Topic 718 applies to all share-based payment tra nsactions in which a grantor acquires goods or services to be used or consumed in a grantor’s own operations by issuing share-based payment awards. The ASU is effective for all entities for fiscal years beginning after December 15, 2019, and interim period s within those fiscal years, with early adoption permitted. The Company does not anticipate that the adoption of this ASU will have a significant impact on its condensed consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, “Intangibles —Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract”, which requires implementation costs incurred by customers in cloud computing arrangements (i.e., hosting arrangements) to be capitalized under the same premises of authoritative guidance for internal-use software, and deferred over the non-cancellable term of the cloud computing arrangements plus any option renewal periods that are reasonably certain to be exercised by the customer or for which the exercise is controlled by the service provider. The ASU is effective for all entities for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, wi th early adoption permitted. The Company is currently evaluating the impact of this ASU on its financial statements. In August 2018, the FASB issued ASU No. 2018-14, “Compensation—Retirement Benefits—Defined Benefit Plans—General (Subtopic 715-20): Disclos ure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans”. This ASU eliminates requirements for certain disclosures and requires additional disclosures under defined benefit pension plans and other postretirement plans. The ASU is eff ective for all entities for fiscal years beginning after December 15, 2020 on a retrospective basis to all periods presented, with early adoption permitted. The Company is currently evaluating the impact of this ASU on its financial statements.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2019
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	NOTE 22 . SUBSEQUENT EVENT On April 15, 2019 , the Board approved the declaration of a quarterly dividend of $0.50 per share of Moody’s common stock, payable on June 10, 2019 to shareholders of record at the close of business on May 20, 2019 .

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2019
Summary of Significant Accounting Policies [Abstract]
Leases	Leases The Company has operating leases , of which substantially all relate to the lease of office space. The Company’s leases which are classifie d as finance leases are not material to the condensed consolidated financial statements. The Company determines if an arrangement meets the definition of a lease at contract inception. The Company recognizes i n its consolidated balance she et a lease liability and an ROU A sset for all leases with a lease term greater than 12 months. In determining the length of the lease term, the Company utilizes judgment in assess ing the likelihood of whether it is reasonably certain that it will exercise an option to extend or early-terminate a lease, if such options are pr ovided in the lease agreement. ROU A ssets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. ROU A ssets and lease liabilities are recognized at the lease commencem ent date based on the present value of lease payments over the lease term. As substantially all of the Company’s leases do not provide an implicit interest rate, the Company uses its estimated secured incremental borrowing rates at the lease commencement d ate in determining the present value of lease payments. These secured incremental borrowing rates are attributable to the currency in which the lease is denominated. At commencement, the Company’s initial measurement of the ROU A sset is calculated as the p resent value of the remaining lease payments (i.e., lease liability), with additive adjustments reflecting: initial direct costs (e . g ., broker commissions) and prepaid lease payments (if any) ; and reduced by any lease incentives provided by the lessor if: ( i) received before lease commencement or ( ii ) receipt of the lease incentive is cont ingent upon future events for which the occurrence is both probable an d within the Company’s control. Lease expense for minimum operating lease payments is recognized on a straight-line basis over the lease term. This straight-line lease expense represents a single lease cost which is comprised of both an interest accretion component relating to the lease liability and amortization of the ROU Assets. The Company records thi s single lease cost in operating and SG&A expenses. However, in situations where an operating lease ROU A sset has been impaired, the subsequent amortizatio n of the ROU Asset is then recorded on a straight-line basis over the remaining lease term and is com bined with accretion expense on the lease liability to result in single operating lease cost (which subsequent to impairment will no longer follow a straight-line recognition pattern) . The Company has lease agreements which include lease and non-lease comp onents. For the Company’s office space leases, the lease components (e.g., fixed rent payments) and non-lease components (e.g., fixed common-area maintenance costs) are combined and accounted fo r as a single lease component. Variable lease payments (e.g. v ariable common-area-maintenance costs) are only included in the initial measurement of the lease liability to the extent those payments depend on an index or a rate. Variable lease payments not included in the lease liability are recognized in net income i n the period in which the obligation for those payments is incurred.

DESCRIPTION OF BUSINESS AND B_2

DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION (Tables)	3 Months Ended
	Mar. 31, 2019
Description of Business and Basis of Presentation [Abstract]
Schedule of Revenue Reclassification	MIS As previously reported Reclassification As Reclassified MA As previously reported Reclassification As Reclassified CFG RD&A Q1 $ 377.7 $ 11.9 $ 389.6 Q1 $ 269.2 $ (2.1) $ 267.1 Q2 377.6 13.4 391.0 Q2 279.9 (4.0) 275.9 Q3 296.1 11.2 307.3 Q3 282.6 (2.3) 280.3 Q4 282.7 8.6 291.3 Q4 302.4 (5.3) 297.1 Full year 2018 $ 1,334.1 $ 45.1 $ 1,379.2 Full year 2018 $ 1,134.1 $ (13.7) $ 1,120.4 SFG ERS Q1 $ 129.7 $ (11.9) $ 117.8 Q1 $ 100.1 $ 2.1 $ 102.2 Q2 141.6 (13.4) 128.2 Q2 105.5 4.0 109.5 Q3 125.4 (11.2) 114.2 Q3 113.0 2.3 115.3 Q4 129.8 (8.6) 121.2 Q4 118.8 5.3 124.1 Full year 2018 $ 526.5 $ (45.1) $ 481.4 Full year 2018 $ 437.4 $ 13.7 $ 451.1

REVENUES (Tables)

REVENUES (Tables)	3 Months Ended
	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue by Line of Business within Each Reportable Segment	Three Months Ended March 31, 2019 2018 MIS: Corporate finance (CFG) (1) Investment-grade $ 97.4 $ 87.2 High-yield 57.3 57.9 Bank loans 72.6 110.1 Other accounts (2) 128.1 134.4 Total CFG 355.4 389.6 Structured finance (SFG) (1) Asset-backed securities 23.2 28.2 RMBS 23.5 24.3 CMBS 17.7 21.3 Structured credit 35.2 43.4 Other accounts 1.1 0.6 Total SFG 100.7 117.8 Financial institutions (FIG) Banking 79.6 77.0 Insurance 29.0 28.3 Managed investments 4.0 5.7 Other accounts 3.2 3.3 Total FIG 115.8 114.3 Public, project and infrastructure finance (PPIF) Public finance / sovereign 46.2 46.9 Project and infrastructure 46.5 46.3 Total PPIF 92.7 93.2 Total ratings revenue 664.6 714.9 MIS Other 5.5 5.0 Total external revenue 670.1 719.9 Intersegment royalty 32.3 29.8 Total MIS 702.4 749.7 MA: Research, data and analytics (RD&A) (3) 307.7 267.1 Enterprise risk solutions (ERS) (3) 121.9 102.2 Professional services (PS) 42.4 37.5 Total external revenue 472.0 406.8 Intersegment revenue 2.4 5.0 Total MA 474.4 411.8 Eliminations (34.7) (34.8) Total MCO $ 1,142.1 $ 1,126.7 (1) Pursuant to certain organizational realignments in the first quarter of 2019, MIS now reports revenue from REITs, which was previously classified in the SFG LOB, as a component of the CFG LOB. The amounts reclassified were not material and prior year revenue by LOB has been reclassified to conform to this new presentation. (2) Other includes: recurring monitoring fees of a rated debt obligation and/or entities that issue such obligations as well as fees from programs such as commercial paper, medium term notes, and ICRA corporate finance revenue. (3) Pursuant to organizational/product realignments in the first quarter of 2019, revenue relating to the Bureau van Dijk FACT product, a credit assessment and origination software solution, is now reported in the ERS LOB. This revenue was previously reported in the RD&A LOB. Prior year revenue by LOB has been reclassified to conform to this new presentation, and the amounts reclassified were not material.
Revenue by Line of Business within Each Geographical Segment	Three Months Ended March 31, 2019 U.S. Non-U.S. Total MIS: Corporate finance (CFG) (1) $ 242.6 $ 112.8 $ 355.4 Structured finance (SFG) (1) 62.2 38.5 100.7 Financial institutions (FIG) 46.0 69.8 115.8 Public, project and infrastructure finance (PPIF) 60.2 32.5 92.7 Total ratings revenue 411.0 253.6 664.6 MIS Other 0.2 5.3 5.5 Total MIS 411.2 258.9 670.1 MA: Research, data and analytics (RD&A) (2) 134.8 172.9 307.7 Enterprise risk solutions (ERS) (2) 48.4 73.5 121.9 Professional services (PS) 17.7 24.7 42.4 Total MA 200.9 271.1 472.0 Total MCO $ 612.1 $ 530.0 $ 1,142.1 Three Months Ended March 31, 2018 U.S. Non-U.S. Total MIS: Corporate finance (CFG) (1) $ 257.3 $ 132.3 $ 389.6 Structured finance (SFG) (1) 74.0 43.8 117.8 Financial institutions (FIG) 48.5 65.8 114.3 Public, project and infrastructure finance (PPIF) 53.4 39.8 93.2 Total ratings revenue 433.2 281.7 714.9 MIS Other 0.2 4.8 5.0 Total MIS 433.4 286.5 719.9 MA: Research, data and analytics (RD&A) (2) 112.6 154.5 267.1 Enterprise risk solutions (ERS) (2) 38.5 63.7 102.2 Professional services (PS) 13.2 24.3 37.5 Total MA 164.3 242.5 406.8 Total MCO $ 597.7 $ 529.0 $ 1,126.7 (1) Pursuant to certain organizational realignments in the first quarter of 2019, MIS now reports revenue from REITs, which was previously classified in the SFG LOB, as a component of the CFG LOB. The amounts reclassified were not material and prior year revenue by LOB has been reclassified to conform to this new presentation. (2) Pursuant to organizational/product realignments in the first quarter of 2019, revenue relating to the Bureau van Dijk FACT product, a credit assessment and origination software solution, is now reported in the ERS LOB. This revenue was previously reported in the RD&A LOB. Prior year revenue by LOB has been reclassified to conform to this new presentation, and the amounts reclassified were not material.
Consolidated Revenue Information by Geographic Area	Three Months Ended March 31, 2019 2018 Revenue: U.S. $ 612.1 $ 597.7 Non-U.S.: EMEA 332.6 347.3 Asia-Pacific 132.2 120.2 Americas 65.2 61.5 Total Non-U.S. 530.0 529.0 Total $ 1,142.1 $ 1,126.7
Schedule of Transaction and Relationship Revenue	Three Months Ended March 31, 2019 2018 Transaction Relationship Total Transaction Relationship Total Corporate Finance $ 249.5 $ 105.9 $ 355.4 $ 283.4 $ 106.2 $ 389.6 70% 30% 100% 73% 27% 100% Structured Finance $ 57.3 $ 43.4 $ 100.7 $ 74.6 $ 43.2 $ 117.8 57% 43% 100% 63% 37% 100% Financial Institutions $ 47.9 $ 67.9 $ 115.8 $ 50.0 $ 64.3 $ 114.3 41% 59% 100% 44% 56% 100% Public, Project and Infrastructure Finance $ 54.7 $ 38.0 $ 92.7 $ 54.4 $ 38.8 $ 93.2 59% 41% 100% 58% 42% 100% MIS Other $ 0.5 $ 5.0 $ 5.5 $ 0.6 $ 4.4 $ 5.0 9% 91% 100% 12% 88% 100% Total MIS $ 409.9 $ 260.2 $ 670.1 $ 463.0 $ 256.9 $ 719.9 61% 39% 100% 64% 36% 100% Moody's Analytics $ 71.5 (1) $ 400.5 $ 472.0 $ 60.8 (1) $ 346.0 $ 406.8 15% 85% 100% 15% 85% 100% Total Moody's Corporation $ 481.4 $ 660.7 $ 1,142.1 $ 523.8 $ 602.9 $ 1,126.7 42% 58% 100% 46% 54% 100% (1) Revenue from software implementation services and risk management advisory projects, while classified by management as transactional revenue, is recognized over time under the New Revenue Accounting Standard (refer to the following table).
Schedule of Revenue Recognition Timing	Three Months Ended March 31, 2019 MIS MA Total Revenue recognized at a point in time $ 409.9 $ 30.4 $ 440.3 Revenue recognized over time 260.2 441.6 701.8 Total $ 670.1 $ 472.0 $ 1,142.1 Three Months Ended March 31, 2018 MIS MA Total Revenue recognized at a point in time $ 463.0 $ 15.5 $ 478.5 Revenue recognized over time 256.9 391.3 648.2 Total $ 719.9 $ 406.8 $ 1,126.7
Schedule of Changes in the Deferred Revenue Balances	Three Months Ended March 31, 2019 MIS MA Total Balance at January 1, 2019 $ 325.4 $ 750.3 $ 1,075.7 Changes in deferred revenue Revenue recognized that was included in the deferred revenue balance at the beginning of the period (92.8) (306.7) (399.5) Increases due to amounts billable excluding amounts recognized as revenue during the period 155.2 346.7 501.9 Effect of exchange rate changes 0.5 4.6 5.1 Total changes in deferred revenue 62.9 44.6 107.5 Balance at March 31, 2019 $ 388.3 $ 794.9 $ 1,183.2 Deferred revenue - current portion $ 271.6 $ 790.7 $ 1,062.3 Deferred revenue - noncurrent portion $ 116.7 $ 4.2 $ 120.9 Three Months Ended March 31, 2018 MIS MA Total Balance at January 1, 2018 (after New Revenue Accounting Standard transition adjustment) $ 334.7 $ 611.6 $ 946.3 Changes in deferred revenue Revenue recognized that was included in the deferred revenue balance at the beginning of the period (93.4) (252.0) (345.4) Increases due to amounts billable excluding amounts recognized as revenue during the period 154.9 357.9 512.8 Effect of exchange rate changes 1.3 11.5 12.8 Total changes in deferred revenue 62.8 117.4 180.2 Balance at March 31, 2018 $ 397.5 $ 729.0 $ 1,126.5 Deferred revenue - current portion $ 273.4 $ 725.3 $ 998.7 Deferred revenue - noncurrent portion $ 124.1 $ 3.7 $ 127.8
MIS [Member]
Disaggregation of Revenue [Line Items]
Schedule of Expected Recognition Period for the Remaining Performance Obligations	MIS Total Less than 1 year 1 - 5 years 6 - 10 Years 11 - 15 years 16-20 years Over 20 Years $ 151.2 $ 23.5 $ 70.2 $ 41.5 $ 6.5 $ 4.1 $ 5.4
MA [Member]
Disaggregation of Revenue [Line Items]
Schedule of Expected Recognition Period for the Remaining Performance Obligations	MA Total Less than 1 Year 1 - 2 Years Over 2 Years $ 2,053.3 $ 1,334.0 $ 491.0 $ 228.3

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2019
Stock-Based Compensation [Abstract]
Stock-Based Compensation Cost and Associated Tax Benefit	Three Months Ended March 31, 2019 2018 Stock-based compensation expense $ 35.7 $ 35.1 Tax benefit $ 7.8 $ 7.2
Weighted Average Assumptions used in Determining Fair Value for Options Granted	Expected dividend yield 1.15% Expected stock volatility 23.62% Risk-free interest rate 2.60% Expected holding period 6.2 years Grant date fair value $43.10
Stock Option Exercises and Restricted Stock Vesting	Three Months Ended March 31, 2019 2018 Exercise of stock options: Proceeds from stock option exercises $ 11.9 $ 26.6 Aggregate intrinsic value $ 35.6 $ 61.9 Tax benefit realized upon exercise $ 8.5 $ 15.0 Number of shares exercised 0.3 0.5 Vesting of restricted stock: Fair value of shares vested $ 146.5 $ 146.7 Tax benefit realized upon vesting $ 33.6 $ 33.9 Number of shares vested 0.8 0.9 Vesting of performance-based restricted stock: Fair value of shares vested $ 47.5 $ 23.0 Tax benefit realized upon vesting $ 11.5 $ 5.5 Number of shares vested 0.3 0.1

INCOME TAXES (Tables)

INCOME TAXES (Tables)	3 Months Ended
	Mar. 31, 2019
Income Taxes [Abstract]
Income Taxes Paid	Three Months Ended March 31, 2019 2018 Income taxes paid $ 36.9 $ 44.2

WEIGHTED AVERAGE SHARES OUTST_2

WEIGHTED AVERAGE SHARES OUTSTANDING (Tables)	3 Months Ended
	Mar. 31, 2019
Weighted Average Shares Outstanding [Abstract]
Reconciliation of Basic to Diluted Shares Outstanding	Three Months Ended March 31, 2019 2018 Basic 190.4 191.4 Dilutive effect of shares issuable under stock-based compensation plans 2.4 3.1 Diluted 192.8 194.5 Anti-dilutive options to purchase common shares and restricted stock as well as contingently issuable restricted stock which are excluded from the table above 0.4 0.7

CASH EQUIVALENT AND INVESTMEN_2

CASH EQUIVALENT AND INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2019
Cash and Cash Equivalents [Abstract]
Schedule of Cash and Cash Equivalents	As of March 31, 2019 Balance sheet location Cost Gross Unrealized Gains Fair Value Cash and cash equivalents Short-term investments Other assets Certificates of deposit and money market deposit accounts (1) $ 551.0 $ - $ 551.0 $ 432.4 $ 110.9 $ 7.7 Open-ended mutual funds $ 15.6 $ 2.1 $ 17.7 $ - $ 3.1 $ 14.6 As of December 31, 2018 Balance sheet location Cost Gross Unrealized Gains Fair Value Cash and cash equivalents Short-term investments Other assets Money market mutual funds $ 15.2 $ - $ 15.2 $ 15.2 $ - $ - Certificates of deposit and money market deposit accounts (1) $ 1,022.4 $ - $ 1,022.4 $ 904.3 $ 115.8 $ 2.3 Open-ended mutual funds $ 29.5 $ 3.8 $ 33.3 $ - $ 16.7 $ 16.6 (1) Consists of time deposits and money market deposit accounts. The remaining contractual maturities for the certificates of deposits classified as short-term investments were one to 12 months at both March 31, 2019 and December 31, 2018. The remaining contractual maturities for the certificates of deposits classified in other assets are 13 to 32 months at March 31, 2019 and 14 to 36 months at December 31, 2018. Time deposits with a maturity of less than 90 days at time of purchase are classified as cash and cash equivalents.

DERIVATIVE INSTRUMENTS AND HE_2

DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES (Tables)	3 Months Ended
	Mar. 31, 2019
Derivative [Line Items]
Gains and Losses on Derivatives Designated as Hedging Instruments	Amount of Income (Expense) Recognized in the Statements of Operations Total amounts of financial statement line item presented in the statements of operations in which the effects of fair value hedges are recorded Three Months Ended March 31, 2019 2018 Interest expense, net $ (52.5) $ (50.7) Descriptions Location on Consolidated Statements of Operations Net interest settlements and accruals on interest rate swaps Interest expense, net $ (0.2) $ (0.1) Fair value changes on interest rate swaps Interest expense, net $ 10.8 $ (9.2) Fair value changes on hedged debt Interest expense, net $ (10.8) $ 9.2
Amount of Gain/(Loss) Recognized in AOCI on Derivative Net Investment Hedging Relationships (Effectiveness Portion)	Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax Gain/(Loss) Recognized in Income on Derivative (Amount Excluded from Effectiveness Testing) Derivative and Non-Derivative Instruments in Net Investment Hedging Relationships Three Months Ended March 31, Three Months Ended March 31, Three Months Ended March 31, 2019 2018 2019 2018 2019 (2) 2018 Cross currency swaps $ 15.2 $ - - - 8.3 - Long-term debt 8.3 (1) (10.9) - - - - Total net investment hedges $ 23.5 $ (10.9) $ - $ - $ 8.3 $ - Derivatives in Cash Flow Hedging Relationships Cross currency swap $ - $ 1.5 $ 0.1 $ 0.1 $ - $ - Interest rate contracts - - (0.1) - - - Total cash flow hedges $ - $ 1.5 $ - $ 0.1 $ - $ - Total $ 23.5 $ (9.4) $ - $ 0.1 $ 8.3 $ - (1) Due to the Company's adoption of ASU 2018-02 during the first quarter of 2019, $2.5 million related to the tax effect of this net investment hedge was reclassified to retained earnings. Refer to Note 1 for further details. (2) Effective with the adoption of ASU 2017-12, the Company has elected to assess the effectiveness of its net investment hedges based on changes in spot exchange rates. Accordingly, amounts recognized directly into Net Income during the first quarter of 2019 related to its cross-currency swaps represent net periodic interest settlements and accruals, which are recognized in interest expense, net.
Cumulative Amount of Unrecognized Hedge Losses Recorded in Accumulated Other Comprehensive Income	Cumulative Gains/(Losses), net of tax March 31, December 31, 2019 2018 Net investment hedges Cross currency swaps $ 27.5 $ 12.3 FX forwards 23.5 23.5 Long-term debt 2.7 (3.1) Total net investment hedges $ 53.7 $ 32.7 Cash flow hedges Interest rate contracts $ (2.3) $ (2.4) Cross currency swap 2.4 2.5 Total cash flow hedges 0.1 0.1 Total net gain in AOCI $ 53.8 $ 32.8
Summary of Notional Amounts of Outstanding Foreign Exchange Forwards	March 31, December 31, 2019 2018 Notional amount of currency pair: Sell Buy Sell Buy Contracts to sell USD for GBP $ 492.5 £ 371.0 $ 310.3 £ 241.2 Contracts to sell USD for Japanese Yen $ 14.4 ¥ 1,600.0 $ 14.3 ¥ 1,600.0 Contracts to sell USD for Canadian dollars $ 87.4 C$ 115.0 $ 99.0 C$ 130.0 Contracts to sell USD for Singapore dollars $ 35.7 S$ 48.0 $ - S$ - Contracts to sell USD for Euros $ 68.6 € 60.0 $ 212.8 € 184.6 NOTE: € = Euro, £ = British pound, $ = U.S. dollar, ¥ = Japanese Yen, C$ = Canadian dollar, S$= Singapore dollars
Gains and Losses Recognized in Consolidated Statement of Operations on Derivatives Not Designated as Hedging instruments	Three Months Ended March 31, Derivatives Not Designated as Accounting Hedges Location on Statements of Operations 2019 2018 Foreign exchange forwards Other non-operating (expense) income, net $ 1.4 $ (52.3)
Fair Value of Derivative Instruments	Derivative and Non-Derivative Instruments Balance Sheet Location March 31, 2019 December 31, 2018 Assets: Derivatives designated as accounting hedges: Cross-currency swaps designated as net investment hedges Other assets $ 36.7 $ 19.4 Interest rate swaps designated as fair value hedges Other assets 15.3 7.5 Total derivatives designated as accounting hedges 52.0 26.9 Derivatives not designated as accounting hedges: FX forwards on certain assets and liabilities Other current assets 0.3 1.4 Total assets $ 52.3 $ 28.3 Liabilities: Derivatives designated as accounting hedges: Cross-currency swaps designated as net investment hedges Other liabilities - 2.9 Interest rate swaps designated as fair value hedges Other liabilities 2.3 5.3 Total derivatives designated as accounting hedges 2.3 8.2 Non-derivative instrument designated as accounting hedge Long-term debt designated as net investment hedge Long-term debt 561.4 571.6 Derivatives not designated as accounting hedges: FX forwards on certain assets and liabilities Accounts payable and accrued liabilities 10.9 8.2 Total liabilities $ 574.6 $ 588.0
Fair Value Hedge [Member]
Derivative [Line Items]
Schedule of Interest Rate Swap	Hedged Item Nature of Swap Notional Amount Floating Interest Rate As of March 31, 2019 As of December 31, 2018 2010 Senior Notes due 2020 Pay Floating/Receive Fixed $ 500.0 $ 500.0 3-month USD LIBOR 2012 Senior Notes due 2022 Pay Floating/Receive Fixed 330.0 330.0 3-month USD LIBOR 2017 Senior Notes due 2021 Pay Floating/Receive Fixed 500.0 500.0 3-month USD LIBOR 2017 Senior Notes due 2023 Pay Floating/Receive Fixed 250.0 - 3-month USD LIBOR Total $ 1,580.0 $ 1,330.0
Net Investment Hedging [Member]
Derivative [Line Items]
Schedule of Interest Rate Swap	Pay Receive Nature of Swap Notional Amount Weighted Average Interest Rate Notional Amount Weighted Average Interest Rate Pay Fixed/Receive Fixed € 663.6 1.51% $ 750.0 4.13% Pay Floating/Receive Floating 931.2 Based on 3-month EURIBOR 1,080.0 Based on 3-month USD LIBOR Total € 1,594.8 $ 1,830.0

GOODWILL AND OTHER ACQUIRED I_2

GOODWILL AND OTHER ACQUIRED INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2019
Goodwill And Other Acquired Intangible Assets [Abstract]
Activity in Goodwill	Three Months Ended March 31, 2019 MIS MA Consolidated Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Balance at beginning of year $ 257.8 $ - $ 257.8 $ 3,535.7 $ (12.2) $ 3,523.5 $ 3,793.5 $ (12.2) $ 3,781.3 Foreign currency translation adjustments 9.4 - 9.4 (28.2) - (28.2) (18.8) - (18.8) Ending balance $ 267.2 $ - $ 267.2 $ 3,507.5 $ (12.2) $ 3,495.3 $ 3,774.7 $ (12.2) $ 3,762.5 Year ended December 31, 2018 MIS MA Consolidated Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Gross goodwill Accumulated impairment charge Net goodwill Balance at beginning of year $ 285.2 $ - $ 285.2 $ 3,480.2 $ (12.2) $ 3,468.0 $ 3,765.4 $ (12.2) $ 3,753.2 Additions/ adjustments - - - 211.5 - 211.5 211.5 - 211.5 Foreign currency translation adjustments (27.4) - (27.4) (156.0) - (156.0) (183.4) - (183.4) Ending balance $ 257.8 $ - $ 257.8 $ 3,535.7 $ (12.2) $ 3,523.5 $ 3,793.5 $ (12.2) $ 3,781.3
Acquired Intangible Assets and Related Amortization	March 31, December 31, 2019 2018 Customer relationships $ 1,360.7 $ 1,367.5 Accumulated amortization (230.2) (214.2) Net customer relationships 1,130.5 1,153.3 Trade secrets 29.9 29.8 Accumulated amortization (28.3) (28.2) Net trade secrets 1.6 1.6 Software/product technology 349.2 353.3 Accumulated amortization (107.7) (101.8) Net software/product technology 241.5 251.5 Trade names 155.9 155.1 Accumulated amortization (36.5) (34.1) Net trade names 119.4 121.0 Other (1) 70.8 70.4 Accumulated amortization (33.4) (31.7) Net other 37.4 38.7 Total acquired intangible assets, net $ 1,530.4 $ 1,566.1 (1) Other intangible assets primarily consist of databases, covenants not to compete, and acquired ratings methodologies and models.
Amortization Expense Relating to Acquired Intangible Assets	Three Months Ended March 31, 2019 2018 Amortization expense $ 26.4 $ 25.7
Estimated Future Amortization Expense for Acquired Intangible Assets Subject to Amortization	Year Ending December 31, 2019 (after March 31) $ 71.0 2020 100.5 2021 100.3 2022 100.3 2023 97.3 Thereafter 1,061.0 Total estimated future amortization $ 1,530.4

RESTRUCTURING (Tables)

RESTRUCTURING (Tables)	3 Months Ended
	Mar. 31, 2019
Restructuring [Abstract]
Restructuring Expenses Included in Consolidated Statements of Operations	Three Months Ended March 31, 2019 2018 2018 Restructuring Program $ 5.5 $ -
Changes to the Restructuring Liability	Employee Termination Costs Contract Termination Costs Total Restructuring Liability Balance as of December 31, 2018 $ 29.9 $ 12.4 $ 42.3 2018 Restructuring Program: Adoption of New Lease Accounting Standard - (10.9) (1) (10.9) (1) Cost incurred and adjustments 1.8 2.2 (2) 4.0 (2) Cash payments and adjustments (5.9) (0.7) (6.6) Balance as of March 31, 2019 $ 25.8 $ 3.0 $ 28.8 2018 Restructuring Program: Cumulative expense incurred to date $ 34.6 $ 19.6 (1) Upon the adoption of the New Lease Accounting Standard, the Company recorded a reclassification of $10.9 million of liabilities for costs associated with certain real estate leases which were exited in previous years, as a reduction of the ROU Asset capitalized upon adoption. (2) Excludes $1.5 million of non-cash acceleration of amortization of leasehold improvements relating to the rationalization and exit of certain real estate leases.

FAIR VALUE (Tables)

FAIR VALUE (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value [Abstract]
Financial Instruments Carried at Fair Value on Recurring Basis	Fair Value Measurement as of March 31, 2019 Description Balance Level 1 Level 2 Assets: Derivatives (1) $ 52.3 $ - $ 52.3 Mutual funds 17.7 17.7 - Total $ 70.0 $ 17.7 $ 52.3 Liabilities: Derivatives (1) $ 13.2 $ - $ 13.2 Total $ 13.2 $ - $ 13.2 Fair Value Measurement as of December 31, 2018 Description Balance Level 1 Level 2 Assets: Derivatives (1) $ 28.3 $ - $ 28.3 Money market mutual funds 15.2 15.2 - Mutual funds 33.3 33.3 - Total $ 76.8 $ 48.5 $ 28.3 Liabilities: Derivatives (1) $ 16.4 $ - $ 16.4 Total $ 16.4 $ - $ 16.4 (1) Represents FX forwards on certain assets and liabilities as well as interest rate swaps and cross-currency swaps as more fully described in Note 10 to the condensed consolidated financial statements.

OTHER BALANCE SHEET AND STATE_2

OTHER BALANCE SHEET AND STATEMENT OF OPERATIONS INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2019
Other Balance Sheet And Statement Of Operations Information [Abstract]
Additional Details Related to Certain Balance Sheet Captions	March 31, December 31, 2019 2018 Other current assets: Prepaid taxes $ 103.8 $ 100.1 Prepaid expenses 104.4 102.0 Capitalized costs to obtain and fulfill sales contracts 76.4 77.2 Other 2.0 3.0 Total other current assets $ 286.6 $ 282.3 March 31, December 31, 2019 2018 Other assets: Investments in non-consolidated affiliates $ 111.6 $ 104.6 Deposits for real-estate leases 13.7 13.5 Indemnification assets related to acquisitions 16.2 16.1 Mutual funds and fixed deposits 22.3 18.9 Costs to obtain sales contracts 86.1 78.0 Other 71.3 43.2 Total other assets $ 321.2 $ 274.3 March 31, December 31, 2019 2018 Accounts payable and accrued liabilities: Salaries and benefits $ 132.3 $ 112.5 Incentive compensation 51.0 154.5 Customer credits, advanced payments and advanced billings 22.9 20.4 Self-insurance reserves 9.3 10.6 Dividends 4.0 6.5 Professional service fees 58.1 47.7 Interest accrued on debt 36.4 70.5 Accounts payable 19.5 30.1 Income taxes 65.4 71.4 Pension and other retirement employee benefits 6.4 6.4 Accrued royalties 14.0 25.1 Foreign exchange forwards on certain assets and liabilities 10.9 8.2 Restructuring liability 25.6 35.5 Other 81.3 95.8 Total accounts payable and accrued liabilities $ 537.1 $ 695.2 March 31, December 31, 2019 2018 Other liabilities: Pension and other retirement employee benefits $ 256.5 $ 249.2 Deferred rent - non-current portion (1) - 94.3 Interest accrued on UTPs 74.9 69.6 Other tax matters 1.3 1.3 Income tax liability - non-current portion (2) 125.3 125.3 Interest rate swaps 2.3 5.3 Restructuring liability 3.2 6.8 Other 23.1 24.7 Total other liabilities $ 486.6 $ 576.5 (1) Pursuant to the adoption of the New Lease Accounting Standard, deferred rent relating to operating leases was reclassified to operating lease ROU Asset. (2) Primarily reflects the transition tax pursuant to the Tax Act, which was enacted into law in December 2018.
Other Non-Operating	Three Months Ended March 31, 2019 2018 FX loss $ (6.2) $ (5.9) Net periodic pension costs - other component 4.5 2.3 Income from investments in non-consolidated affiliates 1.2 1.3 Other 2.8 3.3 Total $ 2.3 $ 1.0

COMPREHENSIVE INCOME AND ACCU_2

COMPREHENSIVE INCOME AND ACCUMULATED OTHER COMPREHENSIVE INCOME (Tables)	3 Months Ended
	Mar. 31, 2019
Comprehensive Income And Accumulated Other Comprehensive Income [Abstract]
Reclassifications out of AOCI	Three Months Ended March 31, Location in the consolidated statements of operations 2019 2018 Gains (losses) on cash flow hedges Cross-currency swap $ (0.1) $ 0.1 Other non-operating income (expense), net Interest rate contract 0.1 - Interest expense, net Total before income taxes - 0.1 Income tax effect of item above - - Provision for income taxes Total net gains (losses) on cash flow hedges - 0.1 Pension and other retirement benefits Amortization of actuarial losses and prior service costs included in net income (0.5) (0.9) Operating expense Amortization of actuarial losses and prior service costs included in net income (0.3) (0.5) SG&A expense Total before income taxes (0.8) (1.4) Income tax effect of item above 0.2 0.4 Provision for income taxes Total pension and other retirement benefits (0.6) (1.0) Total (losses) gains included in Net Income attributable to reclassifications out of AOCI $ (0.6) $ (0.9)
Components of Accumulated Other Comprehensive Income	Three Months Ended March 31, 2019 Pension and Other Retirement Benefits Gains / (Losses) on Cash Flow Hedges Foreign Currency Translation Adjustments Net Gains / (Losses) on Net Investment Hedges Gains on Available for Sale Securities Total Balance December 31, 2018 $ (53.1) $ 0.1 $ (406.0) $ 32.7 $ - $ (426.3) Other comprehensive income/(loss) before reclassifications 0.8 - (34.3) 23.5 - (10.0) Amounts reclassified from AOCI 0.6 - - - - 0.6 Adoption of ASU 2018-02 (See Note 1) (17.3) - - (2.5) - (19.8) Other comprehensive income/(loss) (15.9) - (34.3) 21.0 - (29.2) Balance March 31, 2019 $ (69.0) $ 0.1 $ (440.3) $ 53.7 $ - $ (455.5) Three Months Ended March 31, 2018 Pension and Other Retirement Benefits Gains / (Losses) on Cash Flow Hedges Foreign Currency Translation Adjustments Net Losses on Net Investment Hedges Gains on Available for Sale Securities Total Balance December 31, 2017 $ (61.5) $ 0.9 $ (112.6) $ (1.3) $ 2.3 $ (172.2) Adoption of ASU 2016-01 relating to financial instruments - - - - (2.3) (2.3) Other comprehensive income/(loss) before reclassifications - 1.5 131.1 (10.9) - 121.7 Amounts reclassified from AOCI 1.0 (0.1) - - - 0.9 Other comprehensive income/(loss) 1.0 1.4 131.1 (10.9) (2.3) 120.3 Balance March 31, 2018 $ (60.5) $ 2.3 $ 18.5 $ (12.2) $ - $ (51.9)

PENSION AND OTHER POST-RETIRE_2

PENSION AND OTHER POST-RETIREMENT BENEFITS (Tables)	3 Months Ended
	Mar. 31, 2019
Pension And Other Retirement Benefits [Abstract]
Components of Net Periodic Benefit Expense Related to Post-Retirement Plans	Three Months Ended March 31, Pension Plans Other Retirement Plans 2019 2018 2019 2018 Components of net periodic expense Service cost $ 4.3 $ 4.8 $ 0.7 $ 0.7 Interest cost 5.1 4.4 0.3 0.3 Expected return on plan assets (5.0) (3.8) - - Amortization of net actuarial loss from earlier periods 0.9 1.6 - - Amortization of net prior service costs from earlier periods (0.1) (0.1) (0.1) (0.1) Net periodic expense $ 5.2 $ 6.9 $ 0.9 $ 0.9

INDEBTEDNESS (Tables)

INDEBTEDNESS (Tables)	3 Months Ended
	Mar. 31, 2019
Indebtedness [Abstract]
Summary of Total Indebtedness	March 31, 2019 Principal Amount Fair Value of Interest Rate Swaps (1) Unamortized (Discount) Premium Unamortized Debt Issuance Costs Carrying Value Notes Payable: 5.50% 2010 Senior Notes, due 2020 $ 500.0 $ (1.5) $ (0.5) $ (0.6) $ 497.4 4.50% 2012 Senior Notes, due 2022 500.0 4.8 (1.5) (1.3) 502.0 4.875% 2013 Senior Notes, due 2024 500.0 - (1.5) (1.9) 496.6 5.25% 2014 Senior Notes (30-Year), due 2044 600.0 - 3.2 (5.4) 597.8 1.75% 2015 Senior Notes, due 2027 561.4 - - (2.9) 558.5 2.75% 2017 Senior Notes, due 2021 500.0 6.9 (0.9) (2.2) 503.8 2.625% 2017 Senior Notes, due 2023 500.0 2.8 (0.8) (2.8) 499.2 3.25% 2017 Senior Notes, due 2028 500.0 - (4.6) (3.6) 491.8 3.25% 2018 Senior Notes, due 2021 300.0 - (0.3) (1.3) 298.4 4.25% 2018 Senior Notes, due 2029 400.0 - (2.9) (3.2) 393.9 4.875% 2018 Senior Notes, due 2048 400.0 - (6.7) (4.1) 389.2 Commercial Paper 320.0 - (1.2) - 318.8 Total debt $ 5,581.4 $ 13.0 $ (17.7) $ (29.3) $ 5,547.4 Current portion (318.8) Total long-term debt $ 5,228.6 December 31, 2018 Principal Amount Fair Value of Interest Rate Swaps (1) Unamortized (Discount) Premium Unamortized Debt Issuance Costs Carrying Value Notes Payable: 5.50% 2010 Senior Notes, due 2020 $ 500.0 $ (3.7) $ (0.6) $ (0.7) $ 495.0 4.50% 2012 Senior Notes, due 2022 500.0 1.9 (1.6) (1.4) 498.9 4.875% 2013 Senior Notes, due 2024 500.0 - (1.5) (2.0) 496.5 2.75% 2014 Senior Notes (5-Year), due 2019 450.0 - (0.1) - 449.9 5.25% 2014 Senior Notes (30-Year), due 2044 600.0 - 3.2 (5.5) 597.7 1.75% 2015 Senior Notes, due 2027 571.6 - - (3.1) 568.5 2.75% 2017 Senior Notes, due 2021 500.0 4.0 (1.0) (2.4) 500.6 2.625% 2017 Senior Notes, due 2023 500.0 - (0.9) (2.8) 496.3 3.25% 2017 Senior Notes, due 2028 500.0 - (4.7) (3.7) 491.6 3.25% 2017 Senior Notes, due 2021 300.0 - (0.4) (1.5) 298.1 4.25% 2018 Senior Notes, due 2029 400.0 - (3.0) (3.3) 393.7 4.875% 2018 Senior Notes, due 2048 400.0 - (6.7) (4.1) 389.2 Total debt $ 5,721.6 $ 2.2 $ (17.3) $ (30.5) $ 5,676.0 Current portion (449.9) Total long-term debt $ 5,226.1 (1) The Company has entered into interest rate swaps on the 2010 Senior Notes, the 2012 Senior Notes, the 2017 Senior Notes due 2021 and the 2017 Senior Notes due 2023 which are more fully discussed in Note 10 above. These amounts represent the cumulative amount of fair value hedging adjustments included in the carrying amount of the hedged debt.
Principal Payments Due on Long-Term Borrowings	Year Ending December 31, 2010 Senior Notes due 2020 2012 Senior Notes due 2022 2013 Senior Notes due 2024 2014 Senior Notes (30-year) due 2044 2015 Senior Notes due 2027 2017 Senior Notes due 2021 2017 Senior Notes due 2023 2017 Senior Notes due 2028 2018 Senior Notes due 2021 2018 Senior Notes due 2029 2018 Senior Notes due 2048 Commercial Paper Total 2019 (After March 31) $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ - $ 320.0 $ 320.0 2020 500.0 - - - - - - - - - - - 500.0 2021 - - - - - 500.0 - - 300.0 - - - 800.0 2022 - 500.0 - - - - - - - - - - 500.0 2023 - - - - - - 500.0 - - - - - 500.0 Thereafter - - 500.0 600.0 561.4 - - 500.0 - 400.0 400.0 - 2,961.4 Total $ 500.0 $ 500.0 $ 500.0 $ 600.0 $ 561.4 $ 500.0 $ 500.0 $ 500.0 $ 300.0 $ 400.0 $ 400.0 $ 320.0 $ 5,581.4
Summary of Components of Interest as Presented in Consolidated Statements of Operations	Three Months Ended March 31, 2019 2018 Income $ 5.0 $ 3.2 Expense on borrowings (46.6) (51.3) UTPs and other tax related liabilities (5.6) 1.8 Net periodic pension costs - interest component (5.6) (4.7) Capitalized 0.3 0.3 Total $ (52.5) $ (50.7)
Interest Paid	Three Months Ended March 31, 2019 2018 Interest paid $ 72.8 $ 80.5
Fair Value and Carrying Value of Long-Term Debt	March 31, 2019 December 31, 2018 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value 5.50% 2010 Senior Notes, due 2020 $ 497.4 $ 519.2 $ 495.0 $ 517.7 4.50% 2012 Senior Notes, due 2022 502.0 526.0 498.9 513.7 4.875% 2013 Senior Notes, due 2024 496.6 537.3 496.5 522.4 2.75% 2014 Senior Notes (5-Year), due 2019 - - 449.9 449.9 5.25% 2014 Senior Notes (30-Year), due 2044 597.8 676.5 597.7 638.1 1.75% 2015 Senior Notes, due 2027 558.5 592.3 568.5 585.3 2.75% 2017 Senior Notes, due 2021 503.8 499.6 500.6 489.7 2.625% 2017 Senior Notes, due 2023 499.2 492.3 496.3 476.9 3.25% 2017 Senior Notes, due 2028 491.8 489.1 491.6 472.8 3.25% 2018 Senior Notes, due 2021 298.4 302.6 298.1 298.6 4.25% 2018 Senior Notes, due 2029 393.9 420.0 393.7 407.6 4.875% 2018 Senior Notes, due 2048 389.2 435.4 389.2 409.8 Total $ 5,228.6 $ 5,490.3 $ 5,676.0 $ 5,782.5

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Components of Lease Cost	Three Months Ended March 31, 2019 Operating lease cost $ 24.6 Short-term lease cost 0.4 Variable least cost 3.6 Total lease cost $ 28.6
Schedule of Operating Leases Information	Three Months Ended March 31, 2019 Cash paid for amounts included in the measurement of operating lease liabilities $ 26.2 Right-of-use assets obtained in exchange for new operating lease liabilities $ 9.0 March 31, 2019 Weighted-average remaining lease term 7.3 years Weighted-average discount rate applied to operating leases 3.6%
Operating Leases, Future Minimum Payment	Year Ending December 31, Operating Leases 2019 (After March 31) $ 80.7 2020 104.8 2021 98.2 2022 85.1 2023 80.6 After 2023 245.1 Total lease payments (undiscounted) 694.5 Less: Interest 83.6 Present value of lease liabilities: $ 610.9 Lease liabilities - current $ 87.4 Lease liabilities - noncurrent $ 523.5

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	3 Months Ended
	Mar. 31, 2019
Segment Information [Abstract]
Financial Information by Segment	Three Months Ended March 31, 2019 2018 MIS MA Eliminations Consolidated MIS MA Eliminations Consolidated Revenue $ 702.4 $ 474.4 $ (34.7) $ 1,142.1 $ 749.7 $ 411.8 $ (34.8) $ 1,126.7 Operating, SG&A 316.8 341.1 (34.7) 623.2 310.4 310.4 (34.8) 586.0 Adjusted Operating Income 385.6 133.3 - 518.9 439.3 101.4 - 540.7 Less: Restructuring 2.7 2.8 - 5.5 Depreciation and amortization 17.0 33.3 - 50.3 16.8 32.3 - 49.1 Acquisition-Related Expenses - 1.4 - 1.4 - 0.8 - 0.8 Operating income $ 365.9 $ 95.8 $ - $ 461.7 $ 422.5 $ 68.3 $ - $ 490.8
Consolidated Revenue Information by Geographic Area	Three Months Ended March 31, 2019 2018 Revenue: U.S. $ 612.1 $ 597.7 Non-U.S.: EMEA 332.6 347.3 Asia-Pacific 132.2 120.2 Americas 65.2 61.5 Total Non-U.S. 530.0 529.0 Total $ 1,142.1 $ 1,126.7

Description of Business and B_3

Description of Business and Basis of Presentation - Schedule of Revenue Reclassification (Detail) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	$ 1,142.1				$ 1,126.7
MIS [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	670.1				719.9
MIS [Member] | Corporate finance (CFG) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	355.4	$ 291.3	$ 307.3	$ 391	389.6	$ 1,379.2
MIS [Member] | Structured Finance (SFG) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	100.7	121.2	114.2	128.2	117.8	481.4
MA [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	472				406.8
MA [Member] | Research, Data And Analytics (RD&A) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	307.7	297.1	280.3	275.9	267.1	1,120.4
MA [Member] | Enterprise Risk Solutions (ERS) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues	$ 121.9	124.1	115.3	109.5	102.2	451.1
As Previously Reported [Member] | MIS [Member] | Corporate finance (CFG) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		282.7	296.1	377.6	377.7	1,334.1
As Previously Reported [Member] | MIS [Member] | Structured Finance (SFG) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		129.8	125.4	141.6	129.7	526.5
As Previously Reported [Member] | MA [Member] | Research, Data And Analytics (RD&A) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		302.4	282.6	279.9	269.2	1,134.1
As Previously Reported [Member] | MA [Member] | Enterprise Risk Solutions (ERS) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		118.8	113	105.5	100.1	437.4
Reclassification [Member] | MIS [Member] | Corporate finance (CFG) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		8.6	11.2	13.4	11.9	45.1
Reclassification [Member] | MIS [Member] | Structured Finance (SFG) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		(8.6)	(11.2)	(13.4)	(11.9)	(45.1)
Reclassification [Member] | MA [Member] | Research, Data And Analytics (RD&A) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		(5.3)	(2.3)	(4)	(2.1)	(13.7)
Reclassification [Member] | MA [Member] | Enterprise Risk Solutions (ERS) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Revenues		$ 5.3	$ 2.3	$ 4	$ 2.1	$ 13.7

Description of Business and B_4

Description of Business and Basis of Presentation - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)	Jan. 01, 2019USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Number of Reportable Segments	2
Operating lease right-of-use assets	$ 508.1
Operating lease liabilities	523.5
Accounting Standards Update 2016-02 (Lease) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Operating lease right-of-use assets		$ 518
Operating lease liabilities		622
Deferred Tax Assets		150
Deferred Tax Liabilities		$ 125
Accounting Standards Update 2018-02 [Member] | Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Item]
Effect of adoption adjustment Reduction to retained earnings	$ (19.8)

Revenues - Revenue by Category

Revenues - Revenue by Category (Detail) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,142.1				$ 1,126.7
Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenues	(34.7)				(34.8)
MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	670.1				719.9
MIS [Member] | Operating Segment [Member]
Disaggregation of Revenue [Line Items]
Revenues	702.4				749.7
MIS [Member] | Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenues	32.3				29.8
MIS [Member] | Corporate finance (CFG) [Member]
Disaggregation of Revenue [Line Items]
Revenues	355.4	$ 291.3	$ 307.3	$ 391	389.6	$ 1,379.2
MIS [Member] | Corporate finance (CFG) [Member] | Investment-grade [Member]
Disaggregation of Revenue [Line Items]
Revenues	97.4				87.2
MIS [Member] | Corporate finance (CFG) [Member] | High-yield [Member]
Disaggregation of Revenue [Line Items]
Revenues	57.3				57.9
MIS [Member] | Corporate finance (CFG) [Member] | Bank loans [Member]
Disaggregation of Revenue [Line Items]
Revenues	72.6				110.1
MIS [Member] | Corporate finance (CFG) [Member] | Other product lines [Member]
Disaggregation of Revenue [Line Items]
Revenues	128.1				134.4
MIS [Member] | Structured Finance (SFG) [Member]
Disaggregation of Revenue [Line Items]
Revenues	100.7	121.2	114.2	128.2	117.8	481.4
MIS [Member] | Structured Finance (SFG) [Member] | Assets-backed Securities [Member]
Disaggregation of Revenue [Line Items]
Revenues	23.2				28.2
MIS [Member] | Structured Finance (SFG) [Member] | RMBS [Member]
Disaggregation of Revenue [Line Items]
Revenues	23.5				24.3
MIS [Member] | Structured Finance (SFG) [Member] | CMBS [Member]
Disaggregation of Revenue [Line Items]
Revenues	17.7				21.3
MIS [Member] | Structured Finance (SFG) [Member] | Structured credit [Member]
Disaggregation of Revenue [Line Items]
Revenues	35.2				43.4
MIS [Member] | Structured Finance (SFG) [Member] | Other product lines [Member]
Disaggregation of Revenue [Line Items]
Revenues	1.1				0.6
MIS [Member] | Financial institutions (FIG) [Member]
Disaggregation of Revenue [Line Items]
Revenues	115.8				114.3
MIS [Member] | Financial institutions (FIG) [Member] | Banking [Member]
Disaggregation of Revenue [Line Items]
Revenues	79.6				77
MIS [Member] | Financial institutions (FIG) [Member] | Insurance [Member]
Disaggregation of Revenue [Line Items]
Revenues	29				28.3
MIS [Member] | Financial institutions (FIG) [Member] | Managed investments [Member]
Disaggregation of Revenue [Line Items]
Revenues	4				5.7
MIS [Member] | Financial institutions (FIG) [Member] | Other product lines [Member]
Disaggregation of Revenue [Line Items]
Revenues	3.2				3.3
MIS [Member] | Public, Project And Infrastructure Finance (PPIF) [Member]
Disaggregation of Revenue [Line Items]
Revenues	92.7				93.2
MIS [Member] | Public, Project And Infrastructure Finance (PPIF) [Member] | Public finance/sovereign [Member]
Disaggregation of Revenue [Line Items]
Revenues	46.2				46.9
MIS [Member] | Public, Project And Infrastructure Finance (PPIF) [Member] | Project and infrastructure [Member]
Disaggregation of Revenue [Line Items]
Revenues	46.5				46.3
MIS [Member] | Rating Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues	664.6				714.9
MIS [Member] | MIS Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	5.5				5
MA [Member]
Disaggregation of Revenue [Line Items]
Revenues	472				406.8
MA [Member] | Operating Segment [Member]
Disaggregation of Revenue [Line Items]
Revenues	474.4				411.8
MA [Member] | Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenues	2.4				5
MA [Member] | Research, Data And Analytics (RD&A) [Member]
Disaggregation of Revenue [Line Items]
Revenues	307.7	297.1	280.3	275.9	267.1	1,120.4
MA [Member] | Enterprise Risk Solutions (ERS) [Member]
Disaggregation of Revenue [Line Items]
Revenues	121.9	$ 124.1	$ 115.3	$ 109.5	102.2	$ 451.1
MA [Member] | Professional Services (PS) [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 42.4				$ 37.5

Revenues - Revenues disaggregat

Revenues - Revenues disaggregated by Line of Business and Geographical Area (Detail) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,142.1				$ 1,126.7
U S
Disaggregation of Revenue [Line Items]
Revenues	612.1				597.7
Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	530				529
MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	670.1				719.9
MIS [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	411.2				433.4
MIS [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	258.9				286.5
MIS [Member] | Corporate finance (CFG) [Member]
Disaggregation of Revenue [Line Items]
Revenues	355.4	$ 291.3	$ 307.3	$ 391	389.6	$ 1,379.2
MIS [Member] | Corporate finance (CFG) [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	242.6				257.3
MIS [Member] | Corporate finance (CFG) [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	112.8				132.3
MIS [Member] | Structured Finance (SFG) [Member]
Disaggregation of Revenue [Line Items]
Revenues	100.7	121.2	114.2	128.2	117.8	481.4
MIS [Member] | Structured Finance (SFG) [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	62.2				74
MIS [Member] | Structured Finance (SFG) [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	38.5				43.8
MIS [Member] | Financial institutions (FIG) [Member]
Disaggregation of Revenue [Line Items]
Revenues	115.8				114.3
MIS [Member] | Financial institutions (FIG) [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	46				48.5
MIS [Member] | Financial institutions (FIG) [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	69.8				65.8
MIS [Member] | Public, Project And Infrastructure Finance (PPIF) [Member]
Disaggregation of Revenue [Line Items]
Revenues	92.7				93.2
MIS [Member] | Public, Project And Infrastructure Finance (PPIF) [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	60.2				53.4
MIS [Member] | Public, Project And Infrastructure Finance (PPIF) [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	32.5				39.8
MIS [Member] | Rating Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues	664.6				714.9
MIS [Member] | Rating Revenue [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	411				433.2
MIS [Member] | Rating Revenue [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	253.6				281.7
MIS [Member] | MIS Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	5.5				5
MIS [Member] | MIS Other [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	0.2				0.2
MIS [Member] | MIS Other [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	5.3				4.8
MA [Member]
Disaggregation of Revenue [Line Items]
Revenues	472				406.8
MA [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	200.9				164.3
MA [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	271.1				242.5
MA [Member] | Research Data And Analytics [Member]
Disaggregation of Revenue [Line Items]
Revenues	307.7	297.1	280.3	275.9	267.1	1,120.4
MA [Member] | Research Data And Analytics [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	134.8				112.6
MA [Member] | Research Data And Analytics [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	172.9				154.5
MA [Member] | Enterprise Risk Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues	121.9	$ 124.1	$ 115.3	$ 109.5	102.2	$ 451.1
MA [Member] | Enterprise Risk Solutions [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	48.4				38.5
MA [Member] | Enterprise Risk Solutions [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	73.5				63.7
MA [Member] | Professional Services [Member]
Disaggregation of Revenue [Line Items]
Revenues	42.4				37.5
MA [Member] | Professional Services [Member] | U S
Disaggregation of Revenue [Line Items]
Revenues	17.7				13.2
MA [Member] | Professional Services [Member] | Non Us [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 24.7				$ 24.3

Revenues - Consolidated Revenue

Revenues - Consolidated Revenue Information by Geographic Area (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segments Geographical Areas [Abstract]
Revenues	$ 1,142.1	$ 1,126.7
MIS [Member]
Segments Geographical Areas [Abstract]
Revenues	670.1	719.9
MA [Member]
Segments Geographical Areas [Abstract]
Revenues	472	406.8
U S
Segments Geographical Areas [Abstract]
Revenues	612.1	597.7
U S | MIS [Member]
Segments Geographical Areas [Abstract]
Revenues	411.2	433.4
U S | MA [Member]
Segments Geographical Areas [Abstract]
Revenues	200.9	164.3
Non Us [Member]
Segments Geographical Areas [Abstract]
Revenues	530	529
Non Us [Member] | MIS [Member]
Segments Geographical Areas [Abstract]
Revenues	258.9	286.5
Non Us [Member] | MA [Member]
Segments Geographical Areas [Abstract]
Revenues	271.1	242.5
Non Us [Member] | EMEA [Member]
Segments Geographical Areas [Abstract]
Revenues	332.6	347.3
Non Us [Member] | EMEA [Member] | MIS [Member]
Segments Geographical Areas [Abstract]
Revenues	148.5	181.1
Non Us [Member] | EMEA [Member] | MA [Member]
Segments Geographical Areas [Abstract]
Revenues	184.1	166.2
Non Us [Member] | Asia Pacific [Member]
Segments Geographical Areas [Abstract]
Revenues	132.2	120.2
Non Us [Member] | Asia Pacific [Member] | MIS [Member]
Segments Geographical Areas [Abstract]
Revenues	78.9	72.6
Non Us [Member] | Asia Pacific [Member] | MA [Member]
Segments Geographical Areas [Abstract]
Revenues	53.3	47.6
Non Us [Member] | Americas [Member]
Segments Geographical Areas [Abstract]
Revenues	65.2	61.5
Non Us [Member] | Americas [Member] | MIS [Member]
Segments Geographical Areas [Abstract]
Revenues	31.5	32.8
Non Us [Member] | Americas [Member] | MA [Member]
Segments Geographical Areas [Abstract]
Revenues	$ 33.7	$ 28.7

Revenues - Transaction and Rela

Revenues - Transaction and Relationship Revenue (Detail) - USD ($) $ in Millions	3 Months Ended					12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 1,142.1				$ 1,126.7
Percentage of Revenues	100.00%				100.00%
MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 670.1				$ 719.9
Percentage of Revenues	100.00%				100.00%
MA [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 472				$ 406.8
Percentage of Revenues	100.00%				100.00%
Corporate finance (CFG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 355.4	$ 291.3	$ 307.3	$ 391	$ 389.6	$ 1,379.2
Percentage of Revenues	100.00%				100.00%
Structured Finance (SFG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 100.7	$ 121.2	$ 114.2	$ 128.2	$ 117.8	$ 481.4
Percentage of Revenues	100.00%				100.00%
Financial institutions (FIG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 115.8				$ 114.3
Percentage of Revenues	100.00%				100.00%
Public, Project And Infrastructure Finance (PPIF) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 92.7				$ 93.2
Percentage of Revenues	100.00%				100.00%
MIS Other [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 5.5				$ 5
Percentage of Revenues	100.00%				100.00%
Transaction Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 481.4				$ 523.8
Percentage of Revenues	42.00%				46.00%
Transaction Revenue [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 409.9				$ 463
Percentage of Revenues	61.00%				64.00%
Transaction Revenue [Member] | MA [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 71.5				$ 60.8
Percentage of Revenues	15.00%				15.00%
Transaction Revenue [Member] | Corporate finance (CFG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 249.5				$ 283.4
Percentage of Revenues	70.00%				73.00%
Transaction Revenue [Member] | Structured Finance (SFG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 57.3				$ 74.6
Percentage of Revenues	57.00%				63.00%
Transaction Revenue [Member] | Financial institutions (FIG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 47.9				$ 50
Percentage of Revenues	41.00%				44.00%
Transaction Revenue [Member] | Public, Project And Infrastructure Finance (PPIF) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 54.7				$ 54.4
Percentage of Revenues	59.00%				58.00%
Transaction Revenue [Member] | MIS Other [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 0.5				$ 0.6
Percentage of Revenues	9.00%				12.00%
Relationship Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 660.7				$ 602.9
Percentage of Revenues	58.00%				54.00%
Relationship Revenue [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 260.2				$ 256.9
Percentage of Revenues	39.00%				36.00%
Relationship Revenue [Member] | MA [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 400.5				$ 346
Percentage of Revenues	85.00%				85.00%
Relationship Revenue [Member] | Corporate finance (CFG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 105.9				$ 106.2
Percentage of Revenues	30.00%				27.00%
Relationship Revenue [Member] | Structured Finance (SFG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 43.4				$ 43.2
Percentage of Revenues	43.00%				37.00%
Relationship Revenue [Member] | Financial institutions (FIG) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 67.9				$ 64.3
Percentage of Revenues	59.00%				56.00%
Relationship Revenue [Member] | Public, Project And Infrastructure Finance (PPIF) [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 38				$ 38.8
Percentage of Revenues	41.00%				42.00%
Relationship Revenue [Member] | MIS Other [Member] | MIS [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 5				$ 4.4
Percentage of Revenues	91.00%				88.00%

Revenues - Revenue Recognition

Revenues - Revenue Recognition Timing (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	$ 1,142.1	$ 1,126.7
At Point in Time [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	440.3	478.5
Over Time [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	701.8	648.2
Moodys Investors Service [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	670.1	719.9
Moodys Investors Service [Member] | At Point in Time [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	409.9	463
Moodys Investors Service [Member] | Over Time [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	260.2	256.9
Moodys Analytics [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	472	406.8
Moodys Analytics [Member] | At Point in Time [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	30.4	15.5
Moodys Analytics [Member] | Over Time [Member]
Change In Contract with Customer Liability [Abstract]
Revenue Recognized	$ 441.6	$ 391.3

Revenues - Schedule of Changes

Revenues - Schedule of Changes in the Deferred Revenue Balances (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Change In Contract with Customer Liability [Abstract]
Total Changes in deferred revenue	$ 103.9	$ 167.7
Deferred revenue - current	1,062.3	998.7	$ 953.4
Deferred revenue - noncurrent	120.9	127.8	$ 122.3
Foreign Exchange [Member]
Change In Contract with Customer Liability [Abstract]
Beginning Balance	1,075.7	946.3
Revenue recognized that was included in the contract liability balance at the beginning of the period	(399.5)	(345.4)
Increases due to billings excluding amounts recognized as revenue during the period	501.9	512.8
Effect of exchange rate changes	5.1	12.8
Total Changes in deferred revenue	107.5	180.2
Ending Balance	1,183.2	1,126.5
MIS [Member]
Change In Contract with Customer Liability [Abstract]
Deferred revenue - current	271.6	273.4
Deferred revenue - noncurrent	116.7	124.1
MIS [Member] | Foreign Exchange [Member]
Change In Contract with Customer Liability [Abstract]
Beginning Balance	325.4	334.7
Revenue recognized that was included in the contract liability balance at the beginning of the period	(92.8)	(93.4)
Increases due to billings excluding amounts recognized as revenue during the period	155.2	154.9
Effect of exchange rate changes	0.5	1.3
Total Changes in deferred revenue	62.9	62.8
Ending Balance	388.3	397.5
MA [Member]
Change In Contract with Customer Liability [Abstract]
Deferred revenue - current	790.7	725.3
Deferred revenue - noncurrent	4.2	3.7
MA [Member] | Foreign Exchange [Member]
Change In Contract with Customer Liability [Abstract]
Beginning Balance	750.3	611.6
Revenue recognized that was included in the contract liability balance at the beginning of the period	(306.7)	(252)
Increases due to billings excluding amounts recognized as revenue during the period	346.7	357.9
Effect of exchange rate changes	4.6	11.5
Total Changes in deferred revenue	44.6	117.4
Ending Balance	$ 794.9	$ 729

Revenues - Expected Recognition

Revenues - Expected Recognition Period for Remaining Performance Obligations (Detail) $ in Millions	Mar. 31, 2019USD ($)
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-03-31
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 151.2
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	0 years
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 23.5
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 70.2
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 41.5
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 6.5
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2034-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 4.1
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years
MIS [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2039-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 5.4
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years
MA [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-03-31
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 2,053.3
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	0 years
MA [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 1,334
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
MA [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-04-01
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 491
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
MA [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-03-31
Disaggregation of Revenue [Line Items]
Remaining Performance Obligation	$ 228.3
Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year

Revenues - Additional Informati

Revenues - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
MIS [Member]
Disaggregation of Revenue [Line Items]
Unbilled Receivables	$ 364.9	$ 311.8
MA [Member]
Disaggregation of Revenue [Line Items]
Unbilled Receivables	$ 53.3	$ 59.5

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-Based Compensation Cost and Associated Tax Benefit (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Employee Service Share-based Compensation, Aggregate Disclosures [Abstract]
Stock-based compensation expense	$ 35.7	$ 35.1
Tax benefit	$ 7.8	$ 7.2

Stock-Based Compensation - Weig

Stock-Based Compensation - Weighted Average Assumptions used in Determining Fair Value for Options Granted (Detail)	3 Months Ended
	Mar. 31, 2019$ / shares
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected dividend yield	1.15%
Expected stock volatility	23.62%
Risk-free interest rate	2.60%
Expected holding period	6 years 2 months 12 days
Grant date fair value	$ 43.1

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Proceeds from stock option exercises	$ 11.9	$ 26.6
Aggregate intrinsic value	35.6	61.9
Tax benefit realized upon exercise	$ 8.5	$ 15
Number of shares exercised	0.3	0.5
Restricted Stock [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Fair value of shares vested	$ 146.5	$ 146.7
Tax benefit realized upon vesting	$ 33.6	$ 33.9
Number of shares vested	0.8	0.9
Vesting of Performance Based Restricted Stock [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Fair value of shares vested	$ 47.5	$ 23
Tax benefit realized upon vesting	$ 11.5	$ 5.5
Number of shares vested	0.3	0.1

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employee stock options, granted | shares	0.2
Employee stock options, weighted average grant date fair value | $ / shares	$ 43.1
Employee Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period (in years)	4 years
Unrecognized compensation expense | $	$ 11.4
Weighted average period to recognize expense	2 years 3 months 18 days
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Other than options, Shares granted | shares	0.8
Other than options, weighted average grant date fair value | $ / shares	$ 173.58
Award vesting period (in years)	4 years
Unrecognized compensation expense | $	$ 239.2
Weighted average period to recognize expense	2 years 8 months 12 days
Performance Based Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Other than options, Shares granted | shares	0.1
Other than options, weighted average grant date fair value | $ / shares	$ 167.82
Award vesting period (in years)	3 years
Unrecognized compensation expense | $	$ 40.8
Weighted average period to recognize expense	2 years 2 months 12 days

Income Taxes - Income Taxes Pai

Income Taxes - Income Taxes Paid (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Taxes Paid, Net [Abstract]
Income Taxes Paid	$ 36.9	$ 44.2

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Tax - Additional Information [Abstract]
Effective tax rate	9.20%	14.60%
Overall increase (decrease) in unrecognized tax benefits (UTPs)	$ 20.2
Excess Tax Benefit from Share Based Compensation	26.6
Reductions to Tax Positions	37.3
Net of Federal Tax [Member]
Income Tax - Additional Information [Abstract]
Overall increase (decrease) in unrecognized tax benefits (UTPs)	$ 20.2

Weighted Average Shares Outst_3

Weighted Average Shares Outstanding- Reconciliation of Basic to Diluted Shares Outstanding (Detail) - shares shares in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Basic	190.4	191.4
Dilutive effect of shares issuable under stock-based compensation plans	2.4	3.1
Diluted	192.8	194.5
Anti-dilutive options to purchase common shares and restricted stock as well as contingently issuable restricted stock which are excluded from the table above	0.4	0.7

Accelerated Share Repurchase _2

Accelerated Share Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	Apr. 26, 2019	Mar. 31, 2019	Apr. 26, 2019	Feb. 20, 2019
Accelerated Share Repurchases [Line Items]
Accelerated Share Repurchases Payment				$ 500
Subsequent Event [Member]
Accelerated Share Repurchases [Line Items]
Treasury Stock Shares Acquired			2.8
Accelerated Share Repurchases, Final Price Paid Per Share			$ 180.33
February 20, 2019 [Member]
Accelerated Share Repurchases [Line Items]
Treasury Stock Shares Acquired		2.2
April 26, 2019 [Member] | Subsequent Event [Member]
Accelerated Share Repurchases [Line Items]
Treasury Stock Shares Acquired	0.6

Cash Equivalent and Investmen_3

Cash Equivalent and Investments (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Cash and Cash Equivalents [Line Items]
Fair value	$ 17.7	$ 33.3
Cash and cash equivalents	1,196.6	1,685	$ 1,277.3	$ 1,071.5
Short-term investments	114	132.5
Money Market [Member]
Cash and Cash Equivalents [Line Items]
Cost		15.2
Fair value		15.2
Cash and cash equivalents		15.2
Certificates Of Deposit [Member]
Cash and Cash Equivalents [Line Items]
Cost	551	1,022.4
Fair value	551	1,022.4
Cash and cash equivalents	432.4	904.3
Short-term investments	110.9	115.8
Other assets	7.7	2.3
Open Ended Mutual Funds [Member]
Cash and Cash Equivalents [Line Items]
Cost	15.6	29.5
Gross unrealized gain	2.1	3.8
Fair value	17.7	33.3
Short-term investments	3.1	16.7
Other assets	$ 14.6	$ 16.6

Cash Equivalent and Investmen_4

Cash Equivalent and Investments (Parenthetical) (Detail) - Certificates Of Deposit [Member]	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Short Term Investments [Member] | Minimum [Member]
Cash and Cash Equivalents [Line Items]
Securities Maturity period	1 month	1 month
Short Term Investments [Member] | Maximum [Member]
Cash and Cash Equivalents [Line Items]
Securities Maturity period	12 months	12 months
Cash And Cash Equivalents [Member] | Maximum [Member]
Cash and Cash Equivalents [Line Items]
Securities Maturity period	90 days	90 days
Other Assets [Member] | Minimum [Member]
Cash and Cash Equivalents [Line Items]
Securities Maturity period	13 months	14 months
Other Assets [Member] | Maximum [Member]
Cash and Cash Equivalents [Line Items]
Securities Maturity period	32 months	36 months

Derivative Instruments And He_3

Derivative Instruments And Hedging Activities - Schedule of Interest Rate Swap (Details) - Fair Value Hedge [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Derivative Instrument Detail [Abstract]
Notional amount	$ 1,580	$ 1,330
2010 Senior Notes [Member]
Derivative Instrument Detail [Abstract]
Hedged Item	2010 Senior Notes due 2020
Nature of Swap	Pay Floating/Receive Fixed
Notional amount	$ 500	500
Floating Interest Rate	3-month USD LIBOR
2012 Senior Notes [Member]
Derivative Instrument Detail [Abstract]
Hedged Item	2012 Senior Notes due 2022
Nature of Swap	Pay Floating/Receive Fixed
Notional amount	$ 330	330
Floating Interest Rate	3-month USD LIBOR
2017 Senior Notes [Member]
Derivative Instrument Detail [Abstract]
Hedged Item	2017 Senior Notes due 2021
Nature of Swap	Pay Floating/Receive Fixed
Notional amount	$ 500	$ 500
Floating Interest Rate	3-month USD LIBOR
2017 Notes, due 2023 [Member]
Derivative Instrument Detail [Abstract]
Hedged Item	2017 Senior Notes due 2023
Nature of Swap	Pay Floating/Receive Fixed
Notional amount	$ 250
Floating Interest Rate	3-month USD LIBOR

Derivative Instruments And He_4

Derivative Instruments And Hedging Activities - Summary of Net Gain (Loss) on Interest Rate Swaps Designated in Fair Value Hedge (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Summary of Fair Value Hedge Activity [Abstract]
Interest expense, net	$ (52.5)	$ (50.7)
Designated As Hedging Instrument [Member] | Interest Rate Swap [Member] | Interest Expense [Member]
Summary of Fair Value Hedge Activity [Abstract]
Fair value changes on interest rate swaps	10.8	(9.2)
Fair value changes on hedged debt	(10.8)	9.2
Designated As Hedging Instrument [Member] | Interest Rate Swap [Member] | Interest Expense [Member] | Fair Value hedge Net Interest Settlements and Accruals [Member]
Summary of Fair Value Hedge Activity [Abstract]
Amount of gain (loss) recognized in income	$ (0.2)	$ (0.1)

Derivative Instruments And He_5

Derivative Instruments And Hedging Activities - Summary of Notional Amounts of Outstanding Cross Currency Swap (Detail) - Currency Swap [Member] - Net Investment Hedging [Member] € in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019EUR (€)	Mar. 31, 2019USD ($)
1.51% [Member]
Derivative Notional Amount [Abstract]
Nature of Swap	Pay Fixed/Receive Fixed
3-month EURIBOR [Member]
Derivative Notional Amount [Abstract]
Nature of Swap	Pay Floating/Receive Floating
4.13% [Member]
Derivative Notional Amount [Abstract]
Nature of Swap	Pay Fixed/Receive Fixed
3-month U.S. LIBOR [Member]
Derivative Notional Amount [Abstract]
Nature of Swap	Pay Floating/Receive Floating
Cross-Currency Paid [Member]
Derivative Notional Amount [Abstract]
Notional amount | €	€ 1,594.8
Cross-Currency Paid [Member] | 1.51% [Member]
Derivative Notional Amount [Abstract]
Notional amount | €	€ 663.6
Weighted Average Fixed Interest Rate	1.51%	1.51%
Cross-Currency Paid [Member] | 3-month EURIBOR [Member]
Derivative Notional Amount [Abstract]
Notional amount | €	€ 931.2
Weighted Average Floating Interest Rate	Based on 3-month EURIBOR
Currency Received [Member]
Derivative Notional Amount [Abstract]
Notional amount | $		$ 1,830
Currency Received [Member] | 4.13% [Member]
Derivative Notional Amount [Abstract]
Notional amount | $		$ 750
Weighted Average Fixed Interest Rate	4.13%	4.13%
Currency Received [Member] | 3-month U.S. LIBOR [Member]
Derivative Notional Amount [Abstract]
Notional amount | $		$ 1,080
Weighted Average Floating Interest Rate	Based on 3-month USD LIBOR

Derivative Instruments And He_6

Derivative Instruments And Hedging Activities - Gains (Losses) Recognized in AOCI and Reclassified from AOCI on Derivatives (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax	$ 23.5	$ (9.4)
Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax		0.1
Gain/(Loss) Recognized in Income on Derivative (Amount Excluded from Effectiveness Testing)	8.3
Net Investment Hedging [Member]
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax	23.5	(10.9)
Gain/(Loss) Recognized in Income on Derivative (Amount Excluded from Effectiveness Testing)	8.3
Net Investment Hedging [Member] | Long Term Debt [Member]
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax		(10.9)
Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax	8.3
Net Investment Hedging [Member] | Cross-Currency Swap [Member]
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax	15.2
Gain/(Loss) Recognized in Income on Derivative (Amount Excluded from Effectiveness Testing)	8.3
Cash Flow Hedging [Member]
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax		1.5
Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax		0.1
Cash Flow Hedging [Member] | Cross-Currency Swap [Member]
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Recognized in AOCI on Derivative, net of Tax		1.5
Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax	0.1	$ 0.1
Cash Flow Hedging [Member] | Interest Rate Contract [Member]
Gains and Losses on Derivatives Designated as Hedging Instruments [Abstract]
Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax	$ (0.1)

Derivative Instruments And He_7

Derivative Instruments And Hedging Activities - Cumulative Amount of Unrecognized Hedge Losses Recorded in AOCI (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	$ 53.8	$ 32.8
Net Investment Hedging [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	53.7	32.7
Net Investment Hedging [Member] | Foreign Exchange Forward [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	23.5	23.5
Net Investment Hedging [Member] | Long-Term Debt [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	2.7	(3.1)
Net Investment Hedging [Member] | Cross-Currency Swap [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	27.5	12.3
Cash Flow Hedging [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	0.1	0.1
Cash Flow Hedging [Member] | Interest Rate Contract [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	(2.3)	(2.4)
Cash Flow Hedging [Member] | Cross-Currency Swap [Member]
Cumulative Amount of Unrecognized Hedge Losses Recorded In Accumulated Other Comprehensive Income [Abstract]
Cumulative amount of unrecognized hedge losses recorded in AOCI	$ 2.4	$ 2.5

Derivative Instruments And He_8

Derivative Instruments And Hedging Activities - Summary of Notional Amounts of Outstanding Foreign Exchange Forwards, Cash Flow Hedging (Detail) € in Millions, ¥ in Millions, £ in Millions, $ in Millions, $ in Millions, $ in Millions	Mar. 31, 2019CAD ($)	Mar. 31, 2019EUR (€)	Mar. 31, 2019GBP (£)	Mar. 31, 2019JPY (¥)	Mar. 31, 2019SGD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018CAD ($)	Dec. 31, 2018EUR (€)	Dec. 31, 2018GBP (£)	Dec. 31, 2018JPY (¥)	Dec. 31, 2018USD ($)
Contracts to Sell US Dollars for GBP [Member] | Sell [Member]
Derivative Notional Amount [Abstract]
Notional amount						$ 492.5					$ 310.3
Contracts to Sell US Dollars for GBP [Member] | Buy [Member]
Derivative Notional Amount [Abstract]
Notional amount | £			£ 371						£ 241.2
Contracts to Sell USD for JPY [Member] | Sell [Member]
Derivative Notional Amount [Abstract]
Notional amount						14.4					14.3
Contracts to Sell USD for JPY [Member] | Buy [Member]
Derivative Notional Amount [Abstract]
Notional amount | ¥				¥ 1,600						¥ 1,600
Contracts to Sell USD for CAD [Member] | Sell [Member]
Derivative Notional Amount [Abstract]
Notional amount						87.4					99
Contracts to Sell USD for CAD [Member] | Buy [Member]
Derivative Notional Amount [Abstract]
Notional amount	$ 115						$ 130
Contracts to Sell US Dollars for Singapore dollars [Member] | Sell [Member]
Derivative Notional Amount [Abstract]
Notional amount						35.7
Contracts to Sell US Dollars for Singapore dollars [Member] | Buy [Member]
Derivative Notional Amount [Abstract]
Notional amount					$ 48
Contracts to Sell USD for Euros [Member] | Sell [Member]
Derivative Notional Amount [Abstract]
Notional amount						$ 68.6					$ 212.8
Contracts to Sell USD for Euros [Member] | Buy [Member]
Derivative Notional Amount [Abstract]
Notional amount | €		€ 60						€ 184.6

Derivative Instruments And He_9

Derivative Instruments And Hedging Activities - Summary of Net Gain (Loss) on Foreign Exchange Forwards Not Designated as Hedging Instruments (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Other Nonoperating (Expense) Income [Member]
Foreign Exchange Forwards Not Designated as Hedging Instruments [Abstract]
Amount of gain (loss) recognized in income	$ 1.4	$ (52.3)

Derivative Instruments And H_10

Derivative Instruments And Hedging Activities - Fair Value of Derivative Instruments (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivative, Fair Value, Net [Abstract]
Assets	$ 52.3	$ 28.3
Liabilities	574.6	588
Long Term Debt [Member] | Net Investment Hedging [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities	561.4	571.6
Derivatives Designated as Accounting Hedges [Member]
Derivative, Fair Value, Net [Abstract]
Assets	52	26.9
Liabilities	2.3	8.2
Derivatives Designated as Accounting Hedges [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivative, Fair Value, Net [Abstract]
Assets	15.3	7.5
Derivatives Designated as Accounting Hedges [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities	2.3	5.3
Derivatives Designated as Accounting Hedges [Member] | Cross-Currency Swap [Member] | Other Assets [Member] | Net Investment Hedging [Member]
Derivative, Fair Value, Net [Abstract]
Assets	36.7	19.4
Derivatives Designated as Accounting Hedges [Member] | Cross-Currency Swap [Member] | Other Liabilities [Member] | Net Investment Hedging [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities		2.9
Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Other Current Assets [Member]
Derivative, Fair Value, Net [Abstract]
Assets	0.3	1.4
Not Designated as Accounting Hedges [Member] | Foreign Exchange Forward [Member] | Accounts Payable And Accrued Liabilities [Member]
Derivative, Fair Value, Net [Abstract]
Liabilities	$ 10.9	$ 8.2

Derivative Instruments And H_11

Derivative Instruments And Hedging Activities - Additional Information (Detail) - Derivatives Designated as Accounting Hedges [Member] - Cross-Currency Swap [Member] € in Millions	Mar. 31, 2019EUR (€)
Net Investment Hedging [Member] | 2015 Senior Notes [Member]
Derivative [Line Items]
Notional amount	€ 500
2021 [Member]
Derivative [Line Items]
Notional amount	422.5
2022 [Member]
Derivative [Line Items]
Notional amount	287.7
2023 [Member]
Derivative [Line Items]
Notional amount	441.9
2024 [Member]
Derivative [Line Items]
Notional amount	€ 442.6

Goodwill And Other Acquired I_3

Goodwill And Other Acquired Intangible Assets - Activity in Goodwill (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Activity In Goodwill [Abstract]
Beginning balance, Goodwill gross	$ 3,793.5	$ 3,765.4
Ending balance, Goodwill gross	3,774.7	3,793.5
Beginning balance, Accumulated impairment charge	(12.2)	(12.2)
Ending balance, Accumulated impairment charge	(12.2)	(12.2)
Beginning balance, goodwill net	3,781.3	3,753.2
Additions/ adjustments		211.5
Foreign currency translation adjustments	(18.8)	(183.4)
Ending balance, goodwill net	3,762.5	3,781.3
MIS [Member]
Activity In Goodwill [Abstract]
Beginning balance, Goodwill gross	257.8	285.2
Ending balance, Goodwill gross	267.2	257.8
Beginning balance, goodwill net	257.8	285.2
Foreign currency translation adjustments	9.4	(27.4)
Ending balance, goodwill net	267.2	257.8
MA [Member]
Activity In Goodwill [Abstract]
Beginning balance, Goodwill gross	3,535.7	3,480.2
Ending balance, Goodwill gross	3,507.5	3,535.7
Beginning balance, Accumulated impairment charge	(12.2)	(12.2)
Ending balance, Accumulated impairment charge	(12.2)	(12.2)
Beginning balance, goodwill net	3,523.5	3,468
Additions/ adjustments		211.5
Foreign currency translation adjustments	(28.2)	(156)
Ending balance, goodwill net	$ 3,495.3	$ 3,523.5

Goodwill And Other Acquired I_4

Goodwill And Other Acquired Intangible Assets - Acquired Intangible Assets and Related Amortization (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Intangible Assets and Related Amortization [Abstract]
Acquired intangible assets, net	$ 1,530.4	$ 1,566.1
Customer Relationships [Member]
Intangible Assets and Related Amortization [Abstract]
Acquired intangible assets, gross	1,360.7	1,367.5
Accumulated amortization	(230.2)	(214.2)
Acquired intangible assets, net	1,130.5	1,153.3
Trade Secrets [Member]
Intangible Assets and Related Amortization [Abstract]
Acquired intangible assets, gross	29.9	29.8
Accumulated amortization	(28.3)	(28.2)
Acquired intangible assets, net	1.6	1.6
Computer Software Intangible Asset [Member]
Intangible Assets and Related Amortization [Abstract]
Acquired intangible assets, gross	349.2	353.3
Accumulated amortization	(107.7)	(101.8)
Acquired intangible assets, net	241.5	251.5
Trade Names [Member]
Intangible Assets and Related Amortization [Abstract]
Acquired intangible assets, gross	155.9	155.1
Accumulated amortization	(36.5)	(34.1)
Acquired intangible assets, net	119.4	121
Other Intangible Assets [Member]
Intangible Assets and Related Amortization [Abstract]
Acquired intangible assets, gross	70.8	70.4
Accumulated amortization	(33.4)	(31.7)
Acquired intangible assets, net	$ 37.4	$ 38.7

Goodwill And Other Acquired I_5

Goodwill And Other Acquired Intangible Assets - Amortization Expense Relating to Acquired Intangible Assets (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Amortization Expense Relating to Acquired Intangible Assets [Abstract]
Amortization expense	$ 26.4	$ 25.7

Goodwill And Other Acquired I_6

Goodwill And Other Acquired Intangible Assets - Estimated Future Amortization Expense for Acquired Intangible Assets Subject to Amortization (Detail) $ in Millions	Mar. 31, 2019USD ($)
Estimated Future Amortization Expense for Acquired Intangible Assets Subject to Amortization [Abstract]
2019 (After March 31)	$ 71
2020	100.5
2021	100.3
2022	100.3
2023	97.3
Thereafter	1,061
Total estimated future amortization	$ 1,530.4

Restructuring - Restructuring E

Restructuring - Restructuring Expenses Included in Consolidated Statements of Operations (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Restructuring and Related Cost [Abstract]
Restructuring Charges	$ 5.5

Restructuring - Changes in Rest

Restructuring - Changes in Restructuring Liability (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring liability, Beginning Balance	$ 42.3
Adoption of New Lease Accounting Standard	(10.9)
Costs incurred and adjustments	4
Cash payments and adjustments	(6.6)
Restructuring liability, Ending Balance	28.8
Employee Termination Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring liability, Beginning Balance	29.9
Costs incurred and adjustments	1.8
Cash payments and adjustments	(5.9)
Restructuring liability, Ending Balance	25.8
Cumulative expense incurred to date	34.6
Contract Termination Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring liability, Beginning Balance	12.4
Adoption of New Lease Accounting Standard	(10.9)
Costs incurred and adjustments	2.2
Cash payments and adjustments	(0.7)
Restructuring liability, Ending Balance	3
Cumulative expense incurred to date	$ 19.6

Restructuring - Changes in Re_2

Restructuring - Changes in Restructuring Liability (Parenthetical) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Restructuring Cost and Reserve [Line Items]
Reclassification of Liabilities as a reduction of the ROU Asset capitalized upon adoption	$ (10.9)
Contract Termination Cost [Member]
Restructuring Cost and Reserve [Line Items]
Reclassification of Liabilities as a reduction of the ROU Asset capitalized upon adoption	(10.9)
Contract Termination Cost [Member] | Real State [Member] | Accounting Standards Update 2016-02 (Lease) [Member]
Restructuring Cost and Reserve [Line Items]
Reclassification of Liabilities as a reduction of the ROU Asset capitalized upon adoption	$ 10.9

Restructuring - Additional Info

Restructuring - Additional Information (Detail) - USD ($) $ in Millions	Oct. 26, 2018	Mar. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Remaining restructuring liability		$ 28.8	$ 42.3
Payments for Restructuring		6.6
Restructuring Incurred Cost		4
Restructuring Charges		$ 5.5
2018 Restructuring Program [Member] | Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expected Cost	$ 70
Effect On Future Earnings	40
2018 Restructuring Program [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expected Cost	80
Effect On Future Earnings	50
2018 Restructuring Program [Member] | Employee Termination Cost [Member] | Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	35
2018 Restructuring Program [Member] | Employee Termination Cost [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Payments for Restructuring	40
2018 Restructuring Program [Member] | Employee Severance [Member] | Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expected Cost	35
2018 Restructuring Program [Member] | Employee Severance [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expected Cost	40
2018 Restructuring Program [Member] | Real Estate Component [Member] | Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expected Cost	35
2018 Restructuring Program [Member] | Real Estate Component [Member] | Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Expected Cost	$ 40

Fair Value - Financial Instrume

Fair Value - Financial Instruments Carried at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Assets:
Derivative Contracts	$ 52.3	$ 28.3
Money market funds		15.2
Fixed maturity and open ended mutual funds	17.7	33.3
Total, Assets	70	76.8
Liabilities:
Derivatives, Liabilities	13.2	16.4
Total, Liabilities	13.2	16.4
Level 1 [Member]
Assets:
Money market funds		15.2
Fixed maturity and open ended mutual funds	17.7	33.3
Total, Assets	17.7	48.5
Level 2 [Member]
Assets:
Derivative Contracts	52.3	28.3
Total, Assets	52.3	28.3
Liabilities:
Derivatives, Liabilities	13.2	16.4
Total, Liabilities	$ 13.2	$ 16.4

Other Balance Sheet and State_3

Other Balance Sheet and Statement of Operations Information - Additional Details Related to Certain Balance Sheet Captions (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Other current assets:
Prepaid taxes	$ 103.8	$ 100.1
Prepaid expenses	104.4	102
Capitalized costs to obtain and fulfill sales contracts	76.4	77.2
Other	2	3
Total other current assets	286.6	282.3
Other assets
Investments in joint ventures	111.6	104.6
Deposits for real-estate leases	13.7	13.5
Indemnification assets related to acquisitions	16.2	16.1
Mutual funds and fixed deposits	22.3	18.9
Costs to obtain sales contracts	86.1	78
Other	71.3	43.2
Total other assets	321.2	274.3
Accounts payable and accrued liabilities
Salaries and benefits	132.3	112.5
Incentive compensation	51	154.5
Customer credits, advanced payments and advanced billings	22.9	20.4
Self-insurance reserves	9.3	10.6
Dividends	4	6.5
Professional service fees	58.1	47.7
Interest accrued on debt	36.4	70.5
Accounts payable	19.5	30.1
Income taxes	65.4	71.4
Pension and other post retirement employee benefits	6.4	6.4
Foreign exchange forwards on certain assets and liabilities	10.9	8.2
Restructuring liability	25.6	35.5
Accrued royalties	14	25.1
Other	81.3	95.8
Total accounts payable and accrued liabilities	537.1	695.2
Other liabilities
Pension and other post retirement employee benefits	256.5	249.2
Deferred rent-non-current portion		94.3
Interest accrued on UTPs	74.9	69.6
Other tax matters	1.3	1.3
Income tax liability - non-current	125.3	125.3
Interest rate swaps	2.3	5.3
Restructuring liability	3.2	6.8
Other	23.1	24.7
Total other liabilities	$ 486.6	$ 576.5

Other Balance Sheet and State_4

Other Balance Sheet and Statement of Operations Information - Other Non-Operating Interest (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Other Nonoperating Income (Expense) [Abstract]
FX gain/(loss)	$ (6.2)	$ (5.9)
Net periodic pension costs - interest component	4.5	2.3
Joint venture income	1.2	1.3
Other	2.8	3.3
Total	$ 2.3	$ 1

Comprehensive Income And Accu_3

Comprehensive Income And Accumulated Other Comprehensive Income - Reclassification out of AOCI (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flow Hedges, net of tax:
Gains (loss) on cash flow hedges - Pre Tax		$ 0.1
Amount of Gain/(Loss) Reclassified from AOCI into Income, net of Tax		0.1
Pension and Other Post-Retirement Benefits, net of tax:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	$ (0.8)	(1.4)
Amortization of actuarial losses and prior service costs included in net income - Tax	0.2	0.4
Amortization of actuarial losses and prior service costs included in net income - Net of Tax	(0.6)	(1)
(Losses) Income Attributable to Reclassification Out Of AOCI Net Of Tax	(0.6)	(0.9)
Operating Expense [Member]
Pension and Other Post-Retirement Benefits, net of tax:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	(0.5)	(0.9)
SG&A Expense [Member]
Pension and Other Post-Retirement Benefits, net of tax:
Amortization of actuarial losses and prior service costs included in net income - Pre Tax	(0.3)	(0.5)
Currency Swap [Member] | Other Nonoperating Income (Expense) [Member]
Cash Flow Hedges, net of tax:
Gains (loss) on cash flow hedges - Pre Tax	(0.1)	$ 0.1
Interest Rate Contract [Member] | Interest Expense [Member]
Cash Flow Hedges, net of tax:
Gains (loss) on cash flow hedges - Pre Tax	$ 0.1

Comprehensive Income And Accu_4

Comprehensive Income And Accumulated Other Comprehensive Income - Changes in Components of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income [Abstract]
Beginning Balance	$ (426.3)	$ (172.2)
Pension and other retirement benefit plans before reclassification - Net of Tax	0.8
Reclassification adjustment from AOCI, Pension and Other Postretirement Benefit Plans - Net of Tax	0.6	1
Pension and other retirement benefit - Net of Tax	(15.9)	1
Net unrealized gain (losses) on cash flow before reclassification - Net of Tax		1.5
Reclassification of losses included in net income- Net of Tax		(0.1)
Net unrealized gain (losses) on cash flow - Net of Tax		1.4
Foreign currency translation adjustments before reclassification - Net of Tax	(26.7)	136.1
Net gains (losses) on net investment hedges, Net of Tax	23.5	(10.9)
Available for sale securities before reclassification - Net of Tax		(2.3)
Gains on Available for sale securities - Net of Tax		(2.3)
Other comprehensive income/(loss) before reclassifications	(10)	121.7
Amounts reclassified from AOCI	0.6	0.9
Total other comprehensive (loss) income - Net of Tax	(1.8)	127.6
Ending Balance	(455.5)	(51.9)
Parent [Member]
Accumulated Other Comprehensive Income [Abstract]
Net gains (losses) on net investment hedges, Net of Tax	21
Total other comprehensive (loss) income - Net of Tax	(29.2)	120.3
Accounting Standards Update 2018-02 [Member]
Accumulated Other Comprehensive Income [Abstract]
Reclassification adjustment from AOCI, Pension and Other Postretirement Benefit Plans - Net of Tax	(17.3)
Net gains (losses) on net investment hedges, Net of Tax	(2.5)
Other comprehensive income/(loss) before reclassifications	(19.8)
Financial Instruments - Overall (ASU 2016-01) [Member]
Accumulated Other Comprehensive Income [Abstract]
Gains on Available for sale securities - Net of Tax		(2.3)
Other comprehensive income/(loss) before reclassifications		(2.3)
Pension and Other Retirement Benefits [Member]
Accumulated Other Comprehensive Income [Abstract]
Beginning Balance	(53.1)	(61.5)
Ending Balance	(69)	(60.5)
Gains (Losses) on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income [Abstract]
Beginning Balance	0.1	0.9
Ending Balance	0.1	2.3
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income [Abstract]
Beginning Balance	(406)	(112.6)
Ending Balance	(440.3)	18.5
Gains on Available for Sale Securities [Member]
Accumulated Other Comprehensive Income [Abstract]
Beginning Balance		2.3
Net Investment Hedging [Member]
Accumulated Other Comprehensive Income [Abstract]
Beginning Balance	32.7	(1.3)
Ending Balance	$ 53.7	$ (12.2)

Pension and Other Post-Retire_3

Pension and Other Post-Retirement Benefits - Components of Net Periodic Benefit Expense Related to Post-Retirement Plans (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan Net Periodic Benefit Cost [Asbtract]
Interest cost	$ 5.6	$ 4.7
Pension Plans [Member]
Defined Benefit Plan Net Periodic Benefit Cost [Asbtract]
Service cost	4.3	4.8
Interest cost	5.1	4.4
Expected return on plan assets	(5)	(3.8)
Amortization of net actuarial loss from earlier periods	0.9	1.6
Amortization of net prior service costs from earlier periods	(0.1)	(0.1)
Net periodic expense	5.2	6.9
Other Retirement Plans [Member]
Defined Benefit Plan Net Periodic Benefit Cost [Asbtract]
Service cost	0.7	0.7
Interest cost	0.3	0.3
Amortization of net prior service costs from earlier periods	(0.1)	(0.1)
Net periodic expense	$ 0.9	$ 0.9

Pension and Other Post-Retire_4

Pension and Other Post-Retirement Benefits - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Unfunded Pension Plans [Member]
Pension and Other Post-Retirement Benefits - Additional Information [Abstract]
Defined benefit payment amount	$ 2.4
Estimated additional payments in 2019	3
Other Postretirement Benefit Plans Defined Benefit [Member]
Pension and Other Post-Retirement Benefits - Additional Information [Abstract]
Estimated additional payments in 2019	$ 1

Indebtedness - Summary of Total

Indebtedness - Summary of Total Indebtedness (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Summary of Total Indebtedness [Abstract]
Principal Amount	$ 5,581.4	$ 5,721.6
Fair Value of Interest Rate Swap	13	2.2
Unamortized (Discount) Premium	(17.7)	(17.3)
Unamortized Debt Issuance Costs	(29.3)	(30.5)
Total Debt	5,547.4
Current portion	(318.8)
Carrying Amount	5,228.6	5,676
Current portion of long-term debt		(449.9)
Total long-term debt, non-current	5,228.6	5,226.1
Commercial Paper [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	320
Unamortized (Discount) Premium	(1.2)
Total Debt	318.8
5.50% 2010 Senior Notes, due 2020 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	500	500
Fair Value of Interest Rate Swap	(1.5)	(3.7)
Unamortized (Discount) Premium	(0.5)	(0.6)
Unamortized Debt Issuance Costs	(0.6)	(0.7)
Carrying Amount	497.4	495
4.50% 2012 Senior Notes, due 2022 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	500	500
Fair Value of Interest Rate Swap	4.8	1.9
Unamortized (Discount) Premium	(1.5)	(1.6)
Unamortized Debt Issuance Costs	(1.3)	(1.4)
Carrying Amount	502	498.9
4.875% 2013 Senior Notes, due 2024 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	500	500
Unamortized (Discount) Premium	(1.5)	(1.5)
Unamortized Debt Issuance Costs	(1.9)	(2)
Carrying Amount	496.6	496.5
2.75% 2014 Senior Notes (5-Year), due 2019 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount		450
Unamortized (Discount) Premium		(0.1)
Carrying Amount		449.9
5.25% 2014 Senior Notes (30-Year), due 2044 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	600	600
Unamortized (Discount) Premium	3.2	3.2
Unamortized Debt Issuance Costs	(5.4)	(5.5)
Carrying Amount	597.8	597.7
1.75% 2015 Senior Notes, due 2027 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	561.4	571.6
Unamortized Debt Issuance Costs	(2.9)	(3.1)
Carrying Amount	558.5	568.5
2.75% 2017 Senior Notes, due 2021 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	500	500
Fair Value of Interest Rate Swap	6.9	4
Unamortized (Discount) Premium	(0.9)	(1)
Unamortized Debt Issuance Costs	(2.2)	(2.4)
Carrying Amount	503.8	500.6
2.625% 2017 Notes, due 2023 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	500	500
Fair Value of Interest Rate Swap	2.8
Unamortized (Discount) Premium	(0.8)	(0.9)
Unamortized Debt Issuance Costs	(2.8)	(2.8)
Carrying Amount	499.2	496.3
3.25% 2017 Notes, due 2028 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	500	500
Unamortized (Discount) Premium	(4.6)	(4.7)
Unamortized Debt Issuance Costs	(3.6)	(3.7)
Carrying Amount	491.8	491.6
3.25% 2018 Notes, due 2021 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	300	300
Unamortized (Discount) Premium	(0.3)	(0.4)
Unamortized Debt Issuance Costs	(1.3)	(1.5)
Carrying Amount	298.4	298.1
4.25% 2018 Notes, due 2029 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	400	400
Unamortized (Discount) Premium	(2.9)	(3)
Unamortized Debt Issuance Costs	(3.2)	(3.3)
Carrying Amount	393.9	393.7
4.875% 2018 Notes, due 2048 [Member]
Summary of Total Indebtedness [Abstract]
Principal Amount	400	400
Unamortized (Discount) Premium	(6.7)	(6.7)
Unamortized Debt Issuance Costs	(4.1)	(4.1)
Carrying Amount	$ 389.2	$ 389.2

Indebtedness - Summary of Tot_2

Indebtedness - Summary of Total Indebtedness (Parenthetical) (Detail)	Mar. 31, 2019	Dec. 31, 2018
5.50% 2010 Senior Notes, due 2020 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	5.50%	5.50%
4.50% 2012 Senior Notes, due 2022 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	4.50%	4.50%
4.875% 2013 Senior Notes, due 2024 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	4.875%	4.875%
2.75% 2014 Senior Notes (5-Year), due 2019 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate		2.75%
5.25% 2014 Senior Notes (30-Year), due 2044 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	5.25%	5.25%
1.75% 2015 Senior Notes, due 2027 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	1.75%	1.75%
2.75% 2017 Senior Notes, due 2021 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	2.75%	2.75%
2.625% 2017 Notes, due 2023 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	2.625%	2.625%
3.25% 2017 Notes, due 2028 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	3.25%	3.25%
3.25% 2018 Notes, due 2021 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	3.25%	3.25%
4.25% 2018 Notes, due 2029 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	4.25%	4.25%
4.875% 2018 Notes, due 2048 [Member]
Summary of Total Indebtedness [Abstract]
Notes Payable, interest rate	4.875%	4.875%

Indebtedness - Principal Paymen

Indebtedness - Principal Payments Due on Long-Term Borrowings (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Principal Payments Due on Long Term Borrowings [Abstract]
2019 (after March 31,)	$ 320
2020	500
2021	800
2022	500
2023	500
Thereafter	2,961.4
Total principal payment	5,581.4	$ 5,721.6
Commercial Paper [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
2019 (after March 31,)	320
Total principal payment	320
2010 Senior Notes [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
2020	500
Total principal payment	500	500
2012 Senior Notes [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
2022	500
Total principal payment	500	500
2013 Senior Notes [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Thereafter	500
Total principal payment	500	500
2014 Senior Notes (5-Year) [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Total principal payment		450
2014 Senior Notes (30-Year) [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Thereafter	600
Total principal payment	600	600
2015 Senior Notes [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Thereafter	561.4
Total principal payment	561.4	571.6
2.75% 2017 Senior Notes, due 2021 [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
2021	500
Total principal payment	500	500
2.625% 2017 Notes, due 2023 [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
2023	500
Total principal payment	500	500
3.25% 2017 Notes, due 2028 [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Thereafter	500
Total principal payment	500	500
3.25% 2018 Notes, due 2021 [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
2021	300
Total principal payment	300	300
4.25% 2018 Notes, due 2029 [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Thereafter	400
Total principal payment	400	400
4.875% 2018 Notes, due 2048 [Member]
Principal Payments Due on Long Term Borrowings [Abstract]
Thereafter	400
Total principal payment	$ 400	$ 400

Indebtedness - Summary of Compo

Indebtedness - Summary of Components of Interest as Presented in Consolidated Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Components of Interest as Presented in Consolidated Statements of Operations [Abstract]
Income	$ 5	$ 3.2
Expense on borrowings	(46.6)	(51.3)
Income (expense) on UTPs and other tax related liabilities	(5.6)	1.8
Net periodic pension costs - interest component	(5.6)	(4.7)
Capitalized	0.3	0.3
Total	$ (52.5)	$ (50.7)

Indebtedness - Interest Paid (D

Indebtedness - Interest Paid (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Interest Paid [Abstract]
Interest paid	$ 72.8	$ 80.5

Indebtedness - Fair Value and C

Indebtedness - Fair Value and Carrying Value of Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	$ 5,228.6	$ 5,676
Estimated Fair Value	5,490.3	5,782.5
5.50% 2010 Senior Notes, due 2020 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	497.4	495
Estimated Fair Value	519.2	517.7
4.50% 2012 Senior Notes, due 2022 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	502	498.9
Estimated Fair Value	526	513.7
4.875% 2013 Senior Notes, due 2024 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	496.6	496.5
Estimated Fair Value	537.3	522.4
2.75% 2014 Senior Notes (5-Year), due 2019 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt		449.9
Estimated Fair Value		449.9
5.25% 2014 Senior Notes (30-Year), due 2044 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	597.8	597.7
Estimated Fair Value	676.5	638.1
1.75% 2015 Senior Notes, due 2027 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	558.5	568.5
Estimated Fair Value	592.3	585.3
2.75% 2017 Senior Notes, due 2021 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	503.8	500.6
Estimated Fair Value	499.6	489.7
2.625% 2017 Notes, due 2023 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	499.2	496.3
Estimated Fair Value	492.3	476.9
3.25% 2017 Notes, due 2028 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	491.8	491.6
Estimated Fair Value	489.1	472.8
3.25% 2018 Notes, due 2021 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	298.4	298.1
Estimated Fair Value	302.6	298.6
4.25% 2018 Notes, due 2029 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	393.9	393.7
Estimated Fair Value	420	407.6
4.875% 2018 Notes, due 2048 [Member]
Fair Value and Carrying Value of Long-Term Debt [Abstract]
Long term debt	389.2	389.2
Estimated Fair Value	$ 435.4	$ 409.8

Indebtedness - Additional Infor

Indebtedness - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt, aggregate principal amount	$ 5,581.4	$ 5,721.6
Commercial Paper [Member]
Debt Instrument [Line Items]
Debt, aggregate principal amount	$ 318.8
Commercial paper, interest rate	3.03%
Maturity Date	44 days
Commercial Paper [Member] | Date of Issuance [Member]
Debt Instrument [Line Items]
Maturity Date	79 days
2014 Senior Notes (5-Year) [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 450

Leases - Components of Lease Co

Leases - Components of Lease Cost (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Lease Cost [Abstract]
Operating lease cost	$ 24.6
Short-term lease cost	0.4
Variable least cost	3.6
Total lease cost	$ 28.6

Leases - Operating Leases Infor

Leases - Operating Leases Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Operating Leases Information [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 26.2
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 9
Weighted-average remaining lease term	7 years 3 months 18 days
Weighted-average discount rate applied to operating leases	3.60%

Leases - Operating Leases, Futu

Leases - Operating Leases, Future Minimum Payment (Detail) $ in Millions	Mar. 31, 2019USD ($)
Operating Leases, Future Minimum Payment [Abstract]
Remainder of 2019	$ 80.7
2020	104.8
2021	98.2
2022	85.1
2023	80.6
Thereafter	245.1
Total minimum lease payments	694.5
Less: Interest	83.6
Present value of lease liabilities:	610.9
Lease liabilities - current	87.4
Lease liabilities - noncurrent	$ 523.5

Leases - Additional Information

Leases - Additional Information (Detail)	Mar. 31, 2019
Minimum [Member]
Operating Leased Assets [Line Items]
Lessee, Operating Lease, Renewal Term	1 year
Maximum [Member]
Operating Leased Assets [Line Items]
Lessee, Operating Lease, Renewal Term	20 years

Contingencies - Additional Info

Contingencies - Additional Information (Detail) $ in Millions	Mar. 31, 2019USD ($)
Contingencies [Abstract]
Unsupported Allegations of Minimum Underpaid Taxes	$ 120

Segment Information - Financial

Segment Information - Financial Information by Segment (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Financial Information by Segment [Abstract]
Revenues	$ 1,142.1	$ 1,126.7
Operating, SG&A	623.2	586
Adjusted Operating Income	518.9	540.7
Depreciation and amortization	50.3	49.1
Restructuring Charges	5.5
Acquisition-Related Expenses	1.4	0.8
Operating Income	461.7	490.8
Eliminations [Member]
Financial Information by Segment [Abstract]
Revenues	(34.7)	(34.8)
Operating, SG&A	(34.7)	(34.8)
MIS [Member]
Financial Information by Segment [Abstract]
Revenues	670.1	719.9
MIS [Member] | Operating Segment [Member]
Financial Information by Segment [Abstract]
Revenues	702.4	749.7
Operating, SG&A	316.8	310.4
Adjusted Operating Income	385.6	439.3
Depreciation and amortization	17	16.8
Restructuring Charges	2.7
Operating Income	365.9	422.5
MA [Member]
Financial Information by Segment [Abstract]
Revenues	472	406.8
MA [Member] | Operating Segment [Member]
Financial Information by Segment [Abstract]
Revenues	474.4	411.8
Operating, SG&A	341.1	310.4
Adjusted Operating Income	133.3	101.4
Depreciation and amortization	33.3	32.3
Restructuring Charges	2.8
Acquisition-Related Expenses	1.4	0.8
Operating Income	$ 95.8	$ 68.3

Segment Information - Consolida

Segment Information - Consolidated Revenue Information by Geographic Area (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segments Geographical Areas [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	$ 1,142.1	$ 1,126.7
U S
Segments Geographical Areas [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	612.1	597.7
Non Us [Member]
Segments Geographical Areas [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	530	529
Non Us [Member] | EMEA [Member]
Segments Geographical Areas [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	332.6	347.3
Non Us [Member] | Asia-Pacific [Member]
Segments Geographical Areas [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	132.2	120.2
Non Us [Member] | Americas [Member]
Segments Geographical Areas [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax, Total	$ 65.2	$ 61.5

Segment Information - Additiona

Segment Information - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)	Oct. 26, 2018USD ($)
Segment Reporting Information [Line Items]
Operating Segments	2
2018 Restructuring Program [Member] | Minimum [Member]
Segment Reporting Information [Line Items]
Restructuring and Related Cost Expected Cost		$ 70
2018 Restructuring Program [Member] | Maximum [Member]
Segment Reporting Information [Line Items]
Restructuring and Related Cost Expected Cost		$ 80
2018 Restructuring Program [Member] | MIS [Member]
Segment Reporting Information [Line Items]
Cumulative expense incurred to date	$ 34.9
2018 Restructuring Program [Member] | MIS [Member] | Minimum [Member]
Segment Reporting Information [Line Items]
Restructuring and Related Cost Expected Cost	43
2018 Restructuring Program [Member] | MIS [Member] | Maximum [Member]
Segment Reporting Information [Line Items]
Restructuring and Related Cost Expected Cost	48
2018 Restructuring Program [Member] | MA [Member]
Segment Reporting Information [Line Items]
Cumulative expense incurred to date	19.3
2018 Restructuring Program [Member] | MA [Member] | Minimum [Member]
Segment Reporting Information [Line Items]
Restructuring and Related Cost Expected Cost	27
2018 Restructuring Program [Member] | MA [Member] | Maximum [Member]
Segment Reporting Information [Line Items]
Restructuring and Related Cost Expected Cost	$ 32

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Subsequent Event [Member]	Apr. 16, 2019$ / shares
Subsequent Event [Line Items]
Dividend declared, per share	$ 0.5
Dividend declared, declaration date	Apr. 16, 2019
Dividend declared, payable date	Jun. 10, 2019
Dividend declared, record date	May 20, 2019