$MCO
MOODYS CORP /DE/ Stock $mco

$mco Overview Financials Valuation SEC Filings Company Website

2018 Q4 Form 10-K Financial Statement

#000119312519048576 Filed on February 25, 2019

Income Statement

Concept	2018 Q4	2018	2017 Q4
Revenue	$1.060B	$4.443B	$1.166B
YoY Change	-9.05%	5.68%	23.71%
Cost Of Revenue	$304.1M	$1.246B	$336.2M
YoY Change	-9.55%	2.47%	26.72%
Gross Profit	$756.0M	$3.197B	$829.3M
YoY Change	-8.84%	6.99%	22.53%
Gross Profit Margin	71.32%	71.96%	71.15%
Selling, General & Admin	$278.2M	$1.080B	$299.1M
YoY Change	-6.99%	9.53%	18.13%
% of Gross Profit	36.8%	33.78%	36.07%
Research & Development		$51.10M
YoY Change		21.67%
% of Gross Profit		1.6%
Depreciation & Amortization	$48.30M	$191.9M	$49.90M
YoY Change	-3.21%	21.23%	51.67%
% of Gross Profit	6.39%	6.0%	6.02%
Operating Expenses	$326.5M	$2.575B	$349.0M
YoY Change	-6.45%	8.06%	21.99%
Operating Profit	$376.0M	$1.868B	$465.5M
YoY Change	-19.23%	2.58%	-198.39%
Interest Expense	-$72.40M	-$215.0M	-$45.70M
YoY Change	58.42%	2.87%	-480.83%
% of Operating Profit	-19.26%	-11.51%	-9.82%
Other Income/Expense, Net	$17.40M	-$196.0M	-$21.10M
YoY Change	-182.46%	476.47%	379.55%
Pretax Income	$321.6M	$936.0M	$407.7M
YoY Change	-21.12%	-14.83%	-187.58%
Income Tax	$63.20M	$352.0M	$133.6M
% Of Pretax Income	19.65%	37.61%	32.77%
Net Earnings	$251.0M	$1.310B	$25.50M
YoY Change	884.31%	30.87%	-105.95%
Net Earnings / Revenue	23.68%	29.48%	2.19%
Basic Earnings Per Share	$1.31	$6.84	$0.13
Diluted Earnings Per Share	$1.29	$6.74	$0.13
COMMON SHARES
Basic Shares Outstanding	191.3M shares	191.6M shares	191.0M shares
Diluted Shares Outstanding		194.4M shares

Balance Sheet

Concept	2018 Q4	2018	2017 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.818B	$1.818B	$1.183B
YoY Change	53.68%	53.68%	-46.83%
Cash & Equivalents	$1.685B	$1.685B	$1.072B
Short-Term Investments	$133.0M	$133.0M	$112.0M
Other Short-Term Assets	$282.0M	$282.0M	$250.1M
YoY Change	12.75%	12.35%	77.63%
Inventory
Prepaid Expenses	$67.00M		$91.70M
Receivables	$1.287B	$1.287B	$1.147B
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$3.387B	$3.387B	$2.581B
YoY Change	31.25%	31.23%	-20.67%
LONG-TERM ASSETS
Property, Plant & Equipment	$320.0M	$320.0M	$325.1M
YoY Change	-1.57%	-1.54%	-0.25%
Goodwill	$3.781B		$3.753B
YoY Change	0.75%		266.65%
Intangibles	$1.566B		$1.632B
YoY Change	-4.02%		450.47%
Long-Term Investments	$124.0M	$124.0M	$121.0M
YoY Change	2.48%	2.48%	105.08%
Other Assets	$275.0M	$270.0M	$159.9M
YoY Change	71.98%	47.54%	42.51%
Total Long-Term Assets	$5.668B	$6.139B	$5.710B
YoY Change	-0.74%	2.1%	246.92%
TOTAL ASSETS
Total Short-Term Assets	$3.387B	$3.387B	$2.581B
Total Long-Term Assets	$5.668B	$6.139B	$5.710B
Total Assets	$9.526B	$9.526B	$8.594B
YoY Change	10.84%	10.84%	61.32%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$30.00M	$30.00M	$21.80M
YoY Change	37.61%	36.36%	-23.24%
Accrued Expenses	$452.0M	$452.0M	$530.0M
YoY Change	-14.72%	-14.72%	53.18%
Deferred Revenue	$953.0M		$883.6M
YoY Change	7.85%
Short-Term Debt	$0.00	$0.00	$130.0M
YoY Change	-100.0%	-100.0%
Long-Term Debt Due	$450.0M	$450.0M	$299.5M
YoY Change	50.25%	50.0%	-0.17%
Total Short-Term Liabilities	$2.099B	$2.099B	$2.063B
YoY Change	1.73%	1.75%	-15.03%
LONG-TERM LIABILITIES
Long-Term Debt	$5.226B	$5.226B	$5.111B
YoY Change	2.25%	2.25%	66.87%
Other Long-Term Liabilities	$576.0M	$1.193B	$664.0M
YoY Change	-13.25%	0.0%	56.16%
Total Long-Term Liabilities	$5.802B	$6.419B	$5.775B
YoY Change	0.47%	1.82%	65.56%
TOTAL LIABILITIES
Total Short-Term Liabilities	$2.099B	$2.099B	$2.063B
Total Long-Term Liabilities	$5.802B	$6.419B	$5.775B
Total Liabilities	$8.870B	$9.066B	$8.709B
YoY Change	1.85%	1.61%	37.05%
SHAREHOLDERS EQUITY
Retained Earnings	$8.594B		$7.465B
YoY Change	15.12%		11.61%
Common Stock	$604.0M		$532.0M
YoY Change	13.53%		11.48%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$8.313B		$8.153B
YoY Change	1.96%		1.54%
Treasury Stock Shares	151.6M shares		151.9M shares
Shareholders Equity	$459.0M	$460.0M	-$327.7M
YoY Change
Total Liabilities & Shareholders Equity	$9.526B	$9.526B	$8.594B
YoY Change	10.84%	10.84%	61.32%

Cashflow Statement

Concept	2018 Q4	2018	2017 Q4
OPERATING ACTIVITIES
Net Income	$251.0M	$1.310B	$25.50M
YoY Change	884.31%	30.87%	-105.95%
Depreciation, Depletion And Amortization	$48.30M	$191.9M	$49.90M
YoY Change	-3.21%	21.23%	51.67%
Cash From Operating Activities	$376.5M	$1.461B	$411.9M
YoY Change	-8.59%	93.51%	11.26%
INVESTING ACTIVITIES
Capital Expenditures	-$27.50M	$91.00M	-$21.20M
YoY Change	29.72%	0.0%	-30.26%
Acquisitions		$289.0M
YoY Change		-91.77%
Other Investing Activities	-$265.1M	-$316.0M	$8.600M
YoY Change	-3182.56%	-90.51%	-93.62%
Cash From Investing Activities	-$292.6M	-$406.0M	-$12.60M
YoY Change	2222.22%	-88.13%	-112.07%
FINANCING ACTIVITIES
Cash Dividend Paid		$337.2M
YoY Change		16.12%
Common Stock Issuance & Retirement, Net		$203.0M
YoY Change		1.5%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	568.7M	-$412.0M	-296.6M
YoY Change	-291.74%	-125.75%	131.9%
NET CHANGE
Cash From Operating Activities	376.5M	$1.461B	411.9M
Cash From Investing Activities	-292.6M	-$406.0M	-12.60M
Cash From Financing Activities	568.7M	-$412.0M	-296.6M
Net Change In Cash	652.6M	$613.0M	102.7M
YoY Change	535.44%	-162.55%	-70.38%
FREE CASH FLOW
Cash From Operating Activities	$376.5M	$1.461B	$411.9M
Capital Expenditures	-$27.50M	$91.00M	-$21.20M
Free Cash Flow	$404.0M	$1.370B	$433.1M
YoY Change	-6.72%	106.33%	8.11%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2017	us-gaap	Operating Expenses OperatingExpenses	2383300000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	1820800000	USD
CY2017Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	12200000	USD
CY2016Q4	us-gaap	Restructuring Reserve RestructuringReserve	6300000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	31900000	USD
CY2016	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	13300000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-800000	USD
CY2017Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	1000000000	shares
CY2017	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-800000	USD
CY2017	mco	Estimated Repatriation Tax Liability Resulting From The Tax Act Pay Period EstimatedRepatriationTaxLiabilityResultingFromTheTaxActPayPeriod	P8Y
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	0.022	pure
CY2017Q4	us-gaap	Restructuring Reserve RestructuringReserve	400000	USD
CY2018Q4	us-gaap	Restructuring Reserve RestructuringReserve	42300000	USD
CY2018	us-gaap	Direct Operating Costs DirectOperatingCosts	1245500000	USD
CY2017	us-gaap	Direct Operating Costs DirectOperatingCosts	1216600000	USD
CY2018	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	1080100000	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	985900000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	191900000	USD
CY2017	us-gaap	Depreciation And Amortization DepreciationAndAmortization	158300000	USD
CY2018	us-gaap	Operating Expenses OperatingExpenses	2574500000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	1868200000	USD
CY2018	us-gaap	Interest Income Expense Nonoperating Net InterestIncomeExpenseNonoperatingNet	-216000000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	18800000	USD
CY2017	mco	Realized Gain On Foreign Currency Purchase Price Hedge Derivatives RealizedGainOnForeignCurrencyPurchasePriceHedgeDerivatives	111100000	USD
CY2017	us-gaap	Gain Loss On Sale Of Stock In Subsidiary Or Equity Method Investee GainLossOnSaleOfStockInSubsidiaryOrEquityMethodInvestee	59700000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-197200000	USD
CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-34000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	351600000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	1319400000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	1007700000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	9800000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	7100000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	1309600000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	1000600000	USD
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	8300000	USD
CY2017	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	22500000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	3700000	USD
CY2016	us-gaap	Direct Operating Costs DirectOperatingCosts	1019600000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	351700000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	5226100000	USD
CY2016	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	931200000	USD
CY2016	us-gaap	Restructuring Charges RestructuringCharges	12000000	USD
CY2016	us-gaap	Depreciation And Amortization DepreciationAndAmortization	126700000	USD
CY2016	us-gaap	Operating Expenses OperatingExpenses	2953300000	USD
CY2016	us-gaap	Operating Income Loss OperatingIncomeLoss	650900000	USD
CY2016	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	64400000	USD
CY2016	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-92900000	USD
CY2016	us-gaap	Profit Loss ProfitLoss	275800000	USD
CY2016	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	9200000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	266600000	USD
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.84
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.24
CY2016	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.38
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.74
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.15
CY2016	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.36
CY2018Q4	us-gaap	Assets Current AssetsCurrent	3386900000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	320400000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	3781300000	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1566100000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	197200000	USD
CY2018Q4	us-gaap	Assets Assets	9526200000	USD
CY2018Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	695200000	USD
CY2018Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	449900000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	953400000	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	2098500000	USD
CY2018Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	122300000	USD
CY2018Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	494600000	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	576500000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	8869700000	USD
CY2018Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2018Q4	us-gaap	Preferred Stock Value PreferredStockValue		USD
CY2018Q4	us-gaap	Common Stock Value CommonStockValue	3400000	USD
CY2017Q4	us-gaap	Common Stock Value CommonStockValue	3400000	USD
CY2018Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	600900000	USD
CY2018Q4	us-gaap	Treasury Stock Value TreasuryStockValue	8312500000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	459900000	USD
CY2018Q4	us-gaap	Minority Interest MinorityInterest	196600000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	9526200000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	130300000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	122900000	USD
CY2016	us-gaap	Share Based Compensation ShareBasedCompensation	98100000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-98900000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	136100000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	148100000	USD
CY2016	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	104800000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	8400000	USD
CY2016	us-gaap	Proceeds From Sale Maturity And Collection Of Shortterm Investments ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments	699500000	USD
CY2017	us-gaap	Proceeds From Derivative Instrument Investing Activities ProceedsFromDerivativeInstrumentInvestingActivities	111100000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	289300000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	3511000000	USD
CY2016	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	80800000	USD
CY2017	us-gaap	Proceeds From Hedge Investing Activities ProceedsFromHedgeInvestingActivities	2100000	USD
CY2016	us-gaap	Proceeds From Hedge Investing Activities ProceedsFromHedgeInvestingActivities	3800000	USD
CY2016	us-gaap	Payments For Hedge Investing Activities PaymentsForHedgeInvestingActivities	26900000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	70300000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-12100000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-6600000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-134000000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-638400000	USD
CY2017	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	72900000	USD
CY2016	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	74900000	USD
CY2018	mco	Unrecognized Tax Benefits And Other Non Current Tax Liabilities Period Increase Decrease UnrecognizedTaxBenefitsAndOtherNonCurrentTaxLiabilitiesPeriodIncreaseDecrease	58600000	USD
CY2017	mco	Unrecognized Tax Benefits And Other Non Current Tax Liabilities Period Increase Decrease UnrecognizedTaxBenefitsAndOtherNonCurrentTaxLiabilitiesPeriodIncreaseDecrease	63000000	USD
CY2016	mco	Unrecognized Tax Benefits And Other Non Current Tax Liabilities Period Increase Decrease UnrecognizedTaxBenefitsAndOtherNonCurrentTaxLiabilitiesPeriodIncreaseDecrease	2200000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-25900000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	262900000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	25300000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1461100000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	754600000	USD
CY2016	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	115200000	USD
CY2017	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	170100000	USD
CY2016	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	379900000	USD
CY2018	us-gaap	Proceeds From Sale Maturity And Collection Of Shortterm Investments ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments	160600000	USD
CY2017	us-gaap	Proceeds From Sale Maturity And Collection Of Shortterm Investments ProceedsFromSaleMaturityAndCollectionOfShorttermInvestments	238500000	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	5700000	USD
CY2016	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	1500000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-406400000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-3420000000	USD
CY2018	us-gaap	Proceeds From Notes Payable ProceedsFromNotesPayable	1089900000	USD
CY2017	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	300000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Commercial Paper ProceedsFromIssuanceOfCommercialPaper	988700000	USD
CY2017	us-gaap	Proceeds From Issuance Of Commercial Paper ProceedsFromIssuanceOfCommercialPaper	1837100000	USD
CY2018	us-gaap	Repayments Of Commercial Paper RepaymentsOfCommercialPaper	1120000000	USD
CY2017	us-gaap	Repayments Of Commercial Paper RepaymentsOfCommercialPaper	1707200000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	46900000	USD
CY2017	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	55600000	USD
CY2016	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	77800000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	62200000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	48800000	USD
CY2016	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	44400000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	202600000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	199700000	USD
CY2016	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	738800000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	337200000	USD
CY2017	us-gaap	Payments Of Dividends PaymentsOfDividends	290400000	USD
CY2016	us-gaap	Payments Of Dividends PaymentsOfDividends	285100000	USD
CY2018	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	4400000	USD
CY2017	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	3200000	USD
CY2016	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	6700000	USD
CY2017	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	8500000	USD
CY2016	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	45400000	USD
CY2016	us-gaap	Payments Of Merger Related Costs Financing Activities PaymentsOfMergerRelatedCostsFinancingActivities	200000	USD
CY2018	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	10600000	USD
CY2017	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	26700000	USD
CY2016	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	100000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-411500000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1600100000	USD
CY2016	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1042900000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-29700000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	85300000	USD
CY2017	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-980000000	USD
CY2016	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	294100000	USD
CY2015Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1757400000	USD
CY2017	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	1007700000	USD
CY2017	us-gaap	Dividends Dividends	222800000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	123200000	USD
CY2017	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	9300000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	199700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-1500000	USD
CY2017	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	-800000	USD
CY2017	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	189300000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-114900000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	130700000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-15400000	USD
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CY2018	us-gaap	Dividends Dividends	343400000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	202600000	USD
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CY2018	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	-800000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	656500000	USD
CY2018	us-gaap	Increase Decrease In Restructuring Reserve IncreaseDecreaseInRestructuringReserve	41900000	USD
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CY2018Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.01
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CY2017Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
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CY2018Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
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CY2018Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	151598695	shares
CY2017Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	1147200000	USD
CY2017Q4	us-gaap	Other Assets Current OtherAssetsCurrent	250100000	USD
CY2017Q4	us-gaap	Assets Current AssetsCurrent	2580600000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	325100000	USD
CY2017Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1631600000	USD
CY2017Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	159900000	USD
CY2017Q4	us-gaap	Assets Assets	8594200000	USD
CY2017Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	750300000	USD
CY2017Q4	us-gaap	Commercial Paper CommercialPaper	129900000	USD
CY2017Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	299500000	USD
CY2017Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	883600000	USD
CY2017Q4	us-gaap	Liabilities Current LiabilitiesCurrent	2063300000	USD
CY2017Q4	us-gaap	Contract With Customer Liability Noncurrent ContractWithCustomerLiabilityNoncurrent	140000000	USD
CY2017Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	5111100000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	341600000	USD
CY2017Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	389100000	USD
CY2017Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	664000000	USD
CY2017Q4	us-gaap	Liabilities Liabilities	8709100000	USD
CY2017Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2017Q4	us-gaap	Preferred Stock Value PreferredStockValue		USD
CY2017Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	8594200000	USD
CY2018	dei	Document Type DocumentType	10-K
CY2018	dei	Amendment Flag AmendmentFlag	false
CY2018	dei	Document Period End Date DocumentPeriodEndDate	2018-12-31
CY2018	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2018
CY2018	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2018	dei	Trading Symbol TradingSymbol	MCO
CY2018	dei	Entity Registrant Name EntityRegistrantName	MOODYS CORP /DE/
CY2018	dei	Entity Central Index Key EntityCentralIndexKey	0001059556
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CY2018	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2018	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2017Q4	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	143800000	USD
CY2015Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-333000000	USD
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CY2016	us-gaap	Dividends Dividends	293400000	USD
CY2016	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	98400000	USD
CY2016	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	33400000	USD
CY2016	us-gaap	Minority Interest Period Increase Decrease MinorityInterestPeriodIncreaseDecrease	49100000	USD
CY2016	us-gaap	Adjustments To Additional Paid In Capital Tax Effect From Share Based Compensation AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation	32000000	USD
CY2016	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	738800000	USD
CY2016	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent	-64200000	USD
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CY2016	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	6000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	2600000	USD
CY2016	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParent	2800000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	5400000	USD
CY2016	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	100000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	3700000	USD
CY2016	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesTaxPortionAttributableToParent	1800000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	23100000	USD
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CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	3300000	USD
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CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	7200000	USD
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CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	1400000	USD
CY2018	us-gaap	Other Comprehensive Income Derivatives Qualifying As Hedges Tax Portion Attributable To Parent OtherComprehensiveIncomeDerivativesQualifyingAsHedgesTaxPortionAttributableToParent	500000	USD
CY2018Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	242000000	USD
CY2017Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	219500000	USD
CY2018Q4	us-gaap	Furniture And Fixtures Gross FurnitureAndFixturesGross	52600000	USD
CY2017Q4	us-gaap	Furniture And Fixtures Gross FurnitureAndFixturesGross	50500000	USD
CY2018Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	573600000	USD
CY2017Q4	us-gaap	Capitalized Computer Software Gross CapitalizedComputerSoftwareGross	520300000	USD
CY2018Q4	us-gaap	Leasehold Improvements Gross LeaseholdImprovementsGross	242400000	USD
CY2017Q4	us-gaap	Leasehold Improvements Gross LeaseholdImprovementsGross	240800000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1110600000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1031100000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	790200000	USD
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CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	100800000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	100800000	USD
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CY2017	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	107000000	USD
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CY2016Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	12200000	USD
CY2016Q4	us-gaap	Goodwill Goodwill	1023600000	USD
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CY2017Q4	us-gaap	Goodwill Goodwill	3753200000	USD
CY2018Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	12200000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Projected Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation	507600000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Projected Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation	518100000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Accumulated Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation	457800000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Accumulated Benefit Obligation DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation	461500000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Fair Value Of Plan Assets DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets	348200000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Pension Plans With Accumulated Benefit Obligations In Excess Of Plan Assets Aggregate Fair Value Of Plan Assets DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets	357400000	USD
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	191600000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	191100000	shares
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CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2800000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3100000	shares
CY2016	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2700000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	194400000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	194200000	shares
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	195400000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	400000	shares
CY2017	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	600000	shares
CY2016	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	600000	shares
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	33300000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-200000	USD
CY2018	us-gaap	Derivative Instruments Gain Loss Recognized In Income Ineffective Portion And Amount Excluded From Effectiveness Testing Net DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet	11000000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-30100000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-6700000	USD
CY2016	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-5100000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	3700000	USD
CY2017Q4	mco	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Hedging Activities Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromHedgingActivitiesEffectNetOfTax	-300000	USD
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CY2017Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	605900000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	28300000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	588000000	USD
CY2018Q4	us-gaap	Derivative Assets DerivativeAssets	28300000	USD
CY2018Q4	us-gaap	Money Market Funds At Carrying Value MoneyMarketFundsAtCarryingValue	15200000	USD
CY2018Q4	us-gaap	Trading Securities Equity TradingSecuritiesEquity	33300000	USD
CY2018Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	76800000	USD
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CY2018Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	16400000	USD
CY2017Q4	us-gaap	Derivative Assets DerivativeAssets	13000000	USD
CY2017Q4	us-gaap	Money Market Funds At Carrying Value MoneyMarketFundsAtCarryingValue	42200000	USD
CY2017Q4	us-gaap	Trading Securities Equity TradingSecuritiesEquity	21100000	USD
CY2017Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	76300000	USD
CY2017Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	5500000	USD
CY2017Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	5500000	USD
CY2018Q4	mco	Stable Net Asset Value Public Traded Funds StableNetAssetValuePublicTradedFunds	1	USD
CY2018Q4	us-gaap	Prepaid Taxes PrepaidTaxes	100100000	USD
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CY2017Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	91700000	USD
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CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	104600000	USD
CY2017Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	99100000	USD
CY2018Q4	us-gaap	Deposit Assets DepositAssets	13500000	USD
CY2017Q4	us-gaap	Deposit Assets DepositAssets	12300000	USD
CY2018Q4	us-gaap	Business Combination Indemnification Assets Amount As Of Acquisition Date BusinessCombinationIndemnificationAssetsAmountAsOfAcquisitionDate	16100000	USD
CY2017Q4	us-gaap	Business Combination Indemnification Assets Amount As Of Acquisition Date BusinessCombinationIndemnificationAssetsAmountAsOfAcquisitionDate	17000000	USD
CY2018Q4	us-gaap	Long Term Investments LongTermInvestments	18900000	USD
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CY2018Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	43200000	USD
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CY2018Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	112500000	USD
CY2017Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	129600000	USD
CY2018Q4	us-gaap	Accrued Bonuses Current AccruedBonusesCurrent	154500000	USD
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CY2017Q4	mco	Customer Billings And Payments Received In Advance CustomerBillingsAndPaymentsReceivedInAdvance	22200000	USD
CY2018Q4	us-gaap	Self Insurance Reserve Current SelfInsuranceReserveCurrent	10600000	USD
CY2017Q4	us-gaap	Self Insurance Reserve Current SelfInsuranceReserveCurrent	8100000	USD
CY2018Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	6500000	USD
CY2017Q4	us-gaap	Dividends Payable Current DividendsPayableCurrent	6200000	USD
CY2018Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	47700000	USD
CY2017Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	47100000	USD
CY2018Q4	us-gaap	Interest Payable Current InterestPayableCurrent	70500000	USD
CY2017Q4	us-gaap	Interest Payable Current InterestPayableCurrent	73900000	USD
CY2018Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	30100000	USD
CY2017Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	21800000	USD
CY2018Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	71400000	USD
CY2017Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	79200000	USD
CY2018Q4	us-gaap	Restructuring Reserve Current RestructuringReserveCurrent	35500000	USD
CY2018Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Current Liabilities PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities	6400000	USD
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CY2018Q4	us-gaap	Accrued Royalties Current AccruedRoyaltiesCurrent	25100000	USD
CY2017Q4	us-gaap	Accrued Royalties Current AccruedRoyaltiesCurrent	26400000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	95800000	USD
CY2017Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	80800000	USD
CY2018Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	249200000	USD
CY2017Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	244500000	USD
CY2018Q4	us-gaap	Deferred Rent Credit Noncurrent DeferredRentCreditNoncurrent	94300000	USD
CY2017Q4	us-gaap	Deferred Rent Credit Noncurrent DeferredRentCreditNoncurrent	103100000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	69600000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	54700000	USD
CY2018Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	1300000	USD
CY2017Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	1300000	USD
CY2018Q4	us-gaap	Income Tax Examination Liability Refund Adjustment From Settlement With Taxing Authority IncomeTaxExaminationLiabilityRefundAdjustmentFromSettlementWithTaxingAuthority	125300000	USD
CY2017Q4	us-gaap	Income Tax Examination Liability Refund Adjustment From Settlement With Taxing Authority IncomeTaxExaminationLiabilityRefundAdjustmentFromSettlementWithTaxingAuthority	232200000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	24700000	USD
CY2017Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	24700000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Amortization Period CapitalizedContractCostAmortizationPeriod	P7Y
CY2017Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	8100000	USD
CY2016Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	11100000	USD
CY2015Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	19700000	USD
CY2018	us-gaap	Increase Decrease In Self Insurance Reserve IncreaseDecreaseInSelfInsuranceReserve	7200000	USD
CY2017	us-gaap	Increase Decrease In Self Insurance Reserve IncreaseDecreaseInSelfInsuranceReserve	9600000	USD
CY2016	us-gaap	Increase Decrease In Self Insurance Reserve IncreaseDecreaseInSelfInsuranceReserve	12100000	USD
CY2018	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	4700000	USD
CY2017	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	12600000	USD
CY2016	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	20700000	USD
CY2018Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	10600000	USD
CY2017Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	8100000	USD
CY2016Q4	us-gaap	Self Insurance Reserve SelfInsuranceReserve	11100000	USD
CY2018Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	348200000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Fair Value Of Plan Assets DefinedBenefitPlanFairValueOfPlanAssets	357400000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1071500000	USD
CY2017Q4	us-gaap	Short Term Investments ShortTermInvestments	111800000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2051500000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2051500000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax	-274000000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Translation Gain Loss Arising During Period Tax OtherComprehensiveIncomeForeignCurrencyTranslationGainLossArisingDuringPeriodTax	7200000	USD
CY2018	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-281200000	USD
CY2017	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax	166200000	USD
CY2017	us-gaap	Other Comprehensive Income Foreign Currency Translation Gain Loss Arising During Period Tax OtherComprehensiveIncomeForeignCurrencyTranslationGainLossArisingDuringPeriodTax	-23100000	USD
CY2017	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	189300000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax	200000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationBeforeTax	-36600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	-11500000	USD
CY2016	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-27600000	USD
CY2016	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax	-22200000	USD
CY2016	us-gaap	Other Comprehensive Income Foreign Currency Translation Gain Loss Arising During Period Tax OtherComprehensiveIncomeForeignCurrencyTranslationGainLossArisingDuringPeriodTax	5400000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	-400000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Reclassification Adjustment From Aoci Realized Upon Sale Or Liquidation Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationReclassificationAdjustmentFromAOCIRealizedUponSaleOrLiquidationNetOfTax	-36600000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	2300000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	4200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-4800000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	6000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments And Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsAndTax	2000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-3500000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	2000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-3500000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments And Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsAndTax	2600000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	2600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	5600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	4200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	8700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	5400000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	9700000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	5700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	20900000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	300000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1046000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-11800000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1057800000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1212700000	USD
CY2016	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	223200000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	19400000	USD
CY2016	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-18000000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1193300000	USD
CY2016	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	241200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-263800000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	9600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-273400000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	192400000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-12600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	205000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-41600000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	11000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-52600000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4442700000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4204100000	USD
CY2016	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3604200000	USD
CY2018	mco	Percentage Of Revenues PercentageOfRevenues	1	pure
CY2017	mco	Percentage Of Revenues PercentageOfRevenues	1	pure
CY2016	mco	Percentage Of Revenues PercentageOfRevenues	1	pure
CY2018	us-gaap	Contract With Customer Liability Change In Timeframe Performance Obligation Satisfied Revenue Recognized ContractWithCustomerLiabilityChangeInTimeframePerformanceObligationSatisfiedRevenueRecognized	4442700000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Net Current CapitalizedContractCostNetCurrent	77200000	USD
CY2017Q4	us-gaap	Capitalized Contract Cost Net Current CapitalizedContractCostNetCurrent	50500000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Net Noncurrent CapitalizedContractCostNetNoncurrent	78000000	USD
CY2018Q4	us-gaap	Foreign Currency Contracts Liability Fair Value Disclosure ForeignCurrencyContractsLiabilityFairValueDisclosure	8200000	USD
CY2017Q4	us-gaap	Foreign Currency Contracts Liability Fair Value Disclosure ForeignCurrencyContractsLiabilityFairValueDisclosure	2000000	USD
CY2018Q4	us-gaap	Interest Rate Derivative Liabilities At Fair Value InterestRateDerivativeLiabilitiesAtFairValue	5300000	USD
CY2017Q4	us-gaap	Interest Rate Derivative Liabilities At Fair Value InterestRateDerivativeLiabilitiesAtFairValue	3500000	USD
CY2018Q4	us-gaap	Restructuring Reserve Noncurrent RestructuringReserveNoncurrent	6800000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	31900000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0105	pure
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0134	pure
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0183	pure
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.26	pure
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.27	pure
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.32	pure
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0282	pure
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0219	pure
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.016	pure
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	45.73
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	30
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	22.98
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y2M12D
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y6M
CY2016	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y9M18D
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2900000	shares
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	200000	shares
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	900000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2200000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	2200000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1600000	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	57.48
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	167.12
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	45.79
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	69.86
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice	69.3
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	51.81
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P4Y8M12D
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1	P4Y8M12D
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P3Y6M
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	160200000	USD
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue	159200000	USD
CY2018Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	137800000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	38300000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	48800000	USD
CY2016	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	71800000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	98900000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	88300000	USD
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	71300000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	24200000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	31200000	USD
CY2016	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	24300000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	167700000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	453800000	USD
CY2016	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	292900000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	49800000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	30000000	USD
CY2016	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	39500000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	233000000	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	207000000	USD
CY2016	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	102900000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	450500000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	690800000	USD
CY2016	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	435300000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-59100000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	155500000	USD
CY2016	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-125800000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1800000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	17500000	USD
CY2016	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-20300000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-38000000	USD
CY2017	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-84700000	USD
CY2016	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-7000000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	88300000	USD
CY2016	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-153100000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	779100000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	282200000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21	pure
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35	pure
CY2016	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.022	pure
CY2017	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.019	pure
CY2016	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.022	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.018	pure
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.099	pure
CY2016	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	-0.133	pure
CY2016	mco	Effective Income Tax Rate Reconciliation Litigation Settlement EffectiveIncomeTaxRateReconciliationLitigationSettlement	0.274	pure
CY2016	mco	Effective Income Tax Rate Reconciliation Legacy Tax Items EffectiveIncomeTaxRateReconciliationLegacyTaxItems	-0.001	pure
CY2018	mco	Effective Income Tax Rate Reconciliation Change In Income Tax Rate And Repatriation Of Foreign Earnings EffectiveIncomeTaxRateReconciliationChangeInIncomeTaxRateAndRepatriationOfForeignEarnings	-0.028	pure
CY2017	mco	Effective Income Tax Rate Reconciliation Change In Income Tax Rate And Repatriation Of Foreign Earnings EffectiveIncomeTaxRateReconciliationChangeInIncomeTaxRateAndRepatriationOfForeignEarnings	0.17	pure
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.012	pure
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004	pure
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CY2017Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	41900000	USD
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CY2017Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Contingencies DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsContingencies	28600000	USD
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CY2017Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	25600000	USD
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CY2017Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	448200000	USD
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CY2016	mco	Direct Operating Costs Selling General And Administrative Expense DirectOperatingCostsSellingGeneralAndAdministrativeExpense	1950800000	USD
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CY2017Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	5709900000	USD
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CY2017	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	97000000	USD
CY2016	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	95400000	USD
CY2018	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	2	pure
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CY2017Q4	mco	Estimated Liability Of The Tax Act EstimatedLiabilityOfTheTaxAct	245600000	USD
CY2018	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div><p style='text-align:left;margin-top:6pt;margin-bottom:6pt;line-height:13.8pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0pt;' >Concentration of Credit Risk</font></p><p style='text-align:left;margin-top:6pt;margin-bottom:6pt;line-height:13.8pt;' ><font style='font-family:Times New Roman;font-size:10pt;margin-left:0pt;' >Financial instruments that potentially subject the Company to concentration of credit risk principal</font><font style='font-family:Times New Roman;font-size:10pt;' >ly consist of cash and cash equivalents, short-term investments, trade receivables and derivatives.</font></p><p style='text-align:left;margin-top:6pt;margin-bottom:6pt;line-height:13.8pt;' ><font style='font-family:Times New Roman;font-size:10pt;margin-left:0pt;' >The Company manages its credit risk exposure by allocating its cash equivalents among various money market mutual funds, money market deposit accounts, cert</font><font style='font-family:Times New Roman;font-size:10pt;' >ificates of deposits and</font><font style='font-family:Times New Roman;font-size:10pt;' > high-</font><font style='font-family:Times New Roman;font-size:10pt;' >grade commercial paper. Short-term investments primarily consist of certificates of deposit as of </font><font style='font-family:Times New Roman;font-size:10pt;' >December 31,</font><font style='font-family:Times New Roman;font-size:10pt;' > </font><font style='font-family:Times New Roman;font-size:10pt;' >2018</font><font style='font-family:Times New Roman;font-size:10pt;' > and </font><font style='font-family:Times New Roman;font-size:10pt;' >2017</font><font style='font-family:Times New Roman;font-size:10pt;' >. The Company manages its credit risk exposure on cash equivalents and short-term </font><font style='font-family:Times New Roman;font-size:10pt;' >investments by limiting the amount it can invest with any single entity. </font><font style='font-family:Times New Roman;font-size:10pt;' >No customer accounted for </font><font style='font-family:Times New Roman;font-size:10pt;' >10</font><font style='font-family:Times New Roman;font-size:10pt;' >% or more of accounts receivable at </font><font style='font-family:Times New Roman;font-size:10pt;' >December 31,</font><font style='font-family:Times New Roman;font-size:10pt;' > </font><font style='font-family:Times New Roman;font-size:10pt;' >2018</font><font style='font-family:Times New Roman;font-size:10pt;' > or </font><font style='font-family:Times New Roman;font-size:10pt;' >2017</font><font style='font-family:Times New Roman;font-size:10pt;' >.</font></p><p style='text-align:left;margin-top:6pt;margin-bottom:6pt;line-height:13.8pt;' ></p></div>
CY2018	us-gaap	Use Of Estimates UseOfEstimates	<div><p style='text-align:left;margin-top:6pt;margin-bottom:6pt;line-height:13.8pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;margin-left:0pt;' >Use of Estimates</font></p><p style='text-align:left;margin-top:6pt;margin-bottom:6pt;line-height:13.8pt;' ><font style='font-family:Times New Roman;font-size:10pt;margin-left:0pt;' >The p</font><font style='font-family:Times New Roman;font-size:10pt;' >reparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial st</font><font style='font-family:Times New Roman;font-size:10pt;' >atements, and the reported amounts of revenue and expenses during the period. Actual results could differ from those estimates. Estimates are used for, but not limited to, revenue recognition, accounts receivable allowances, income taxes, contingencies, va</font><font style='font-family:Times New Roman;font-size:10pt;' >luation</font><font style='font-family:Times New Roman;font-size:10pt;' > and useful lives</font><font style='font-family:Times New Roman;font-size:10pt;' > of long-lived and intangible assets, goodwill, pension and other retirement benefits, stock-based compensation, </font><font style='font-family:Times New Roman;font-size:10pt;' >restructuring </font><font style='font-family:Times New Roman;font-size:10pt;' >and depreciable lives for property and equipment and computer software.</font></p></div>
CY2018	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<div><table style='border-collapse:collapse;' ><tr style='height:15pt;' ><td style='width:215.25pt;border-bottom-style:solid;border-bottom-width:1;text-align:center;vertical-align:bottom;border-color:Black;min-width:215.25pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;color:#000000;' >Date Authorized</font></td><td style='width:13.5pt;text-align:center;vertical-align:bottom;border-color:Black;min-width:13.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;color:#000000;' ></font></td><td colspan='2' rowspan='1' style='width:132.75pt;border-bottom-style:solid;border-bottom-width:1;text-align:center;vertical-align:bottom;border-color:Black;min-width:132.75pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;color:#000000;' >Amount Authorized</font></td><td style='width:18pt;text-align:center;vertical-align:bottom;border-color:Black;min-width:18pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;color:#000000;' ></font></td><td colspan='2' rowspan='1' style='width:125.25pt;border-bottom-style:solid;border-bottom-width:1;text-align:center;vertical-align:bottom;border-color:Black;min-width:125.25pt;' ><font style='font-family:Times New Roman;font-size:10pt;font-weight:bold;color:#000000;' >Remaining Authority</font></td></tr><tr style='height:15pt;' ><td style='width:215.25pt;border-top-style:solid;border-top-width:1;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:215.25pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >October 22, 2018</font></td><td style='width:13.5pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:13.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:15.75pt;border-top-style:solid;border-top-width:1;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:15.75pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >$</font></td><td style='width:117pt;border-top-style:solid;border-top-width:1;text-align:right;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:117pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >1,000.0</font></td><td style='width:18pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:18pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:15.75pt;border-top-style:solid;border-top-width:1;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:15.75pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >$</font></td><td style='width:109.5pt;border-top-style:solid;border-top-width:1;text-align:right;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:109.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >1,000.0</font></td></tr><tr style='height:15pt;' ><td style='width:215.25pt;text-align:left;vertical-align:bottom;border-color:Black;min-width:215.25pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >December 15, 2015</font></td><td style='width:13.5pt;text-align:left;vertical-align:bottom;border-color:Black;min-width:13.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:15.75pt;text-align:left;vertical-align:bottom;border-color:Black;min-width:15.75pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >$</font></td><td style='width:117pt;text-align:right;vertical-align:bottom;border-color:Black;min-width:117pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >1,000.0</font></td><td style='width:18pt;text-align:left;vertical-align:bottom;border-color:Black;min-width:18pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:15.75pt;border-bottom-style:solid;border-bottom-width:1;text-align:left;vertical-align:bottom;border-color:Black;min-width:15.75pt;' ><font style='font-family:Calibri;font-size:11pt;color:#000000;' ></font></td><td style='width:109.5pt;border-bottom-style:solid;border-bottom-width:1;text-align:right;vertical-align:bottom;border-color:Black;min-width:109.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >324.3</font></td></tr><tr style='height:15.75pt;' ><td style='width:215.25pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:215.25pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >Total Remaining Authority</font></td><td style='width:13.5pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:13.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:15.75pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:15.75pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:117pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:117pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:18pt;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:18pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' ></font></td><td style='width:15.75pt;border-top-style:solid;border-top-width:1;border-bottom-style:double;border-bottom-width:3;text-align:left;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:15.75pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >$</font></td><td style='width:109.5pt;border-top-style:solid;border-top-width:1;border-bottom-style:double;border-bottom-width:3;text-align:right;vertical-align:bottom;background-color:#CCEEFF;border-color:Black;min-width:109.5pt;' ><font style='font-family:Times New Roman;font-size:10pt;color:#000000;' >1,324.3</font></td></tr></table></div>
CY2017Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	151932157	shares
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-1027300000	USD
CY2017	us-gaap	Minority Interest Period Increase Decrease MinorityInterestPeriodIncreaseDecrease	5700000	USD
CY2018	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	pure
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	39500000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	38100000	USD
CY2018Q4	us-gaap	Goodwill Gross GoodwillGross	3793500000	USD
CY2017Q4	us-gaap	Restructuring Reserve Current RestructuringReserveCurrent	400000	USD
CY2016Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.37
CY2016Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.37
CY2016Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.75
CY2017Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.38
CY2017Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.38
CY2017Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.38
CY2016Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.37
CY2016Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.37
CY2016Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.37
CY2016Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.37
CY2017Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.38
CY2017Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.38
CY2017Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.38
CY2017Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.38
CY2015Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	27500000	USD
CY2015Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	4300000	USD
CY2018	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	4200000	USD
CY2017	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-3100000	USD
CY2016	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-26900000	USD
CY2015Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-339500000	USD
CY2016Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-364900000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsNetOfTax	200000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax	6000000	USD
CY2016	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	6200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsNetOfTax	12600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax	5400000	USD
CY2017	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	18000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsNetOfTax	4200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax	4200000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent	8400000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-800000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-2300000	USD
CY2015Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	203400000	USD
CY2018	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	19300000	USD
CY2016	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	19500000	USD
CY2018Q4	us-gaap	Lessee Operating Lease Term Of Contract LesseeOperatingLeaseTermOfContract	P9Y
CY2018Q4	mco	Unsupported Allegations Of Minimum Underpaid Taxes UnsupportedAllegationsOfMinimumUnderpaidTaxes	120000000	USD
CY2017Q4	us-gaap	Defined Benefit Plan Weighted Average Asset Allocations DefinedBenefitPlanWeightedAverageAssetAllocations	1	pure
CY2018Q4	us-gaap	Defined Benefit Plan Weighted Average Asset Allocations DefinedBenefitPlanWeightedAverageAssetAllocations	1	pure
CY2018	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	15400000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	15300000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	7800000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	15300000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	15200000	USD
CY2017Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	975200000	USD
CY2017Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1000500000	USD
CY2017Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1062900000	USD
CY2017Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1165500000	USD
CY2017Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	446700000	USD
CY2017Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	460100000	USD
CY2017Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	448500000	USD
CY2017Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	465500000	USD
CY2017Q1	us-gaap	Net Income Loss NetIncomeLoss	345600000	USD
CY2017Q2	us-gaap	Net Income Loss NetIncomeLoss	312200000	USD
CY2017Q3	us-gaap	Net Income Loss NetIncomeLoss	317300000	USD
CY2017Q4	us-gaap	Net Income Loss NetIncomeLoss	25500000	USD
CY2018Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1126700000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1175100000	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1080800000	USD
CY2018Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1060100000	USD
CY2018Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	490800000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	534000000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	466800000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	376600000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	372900000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	376200000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	310200000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	250300000	USD
CY2017Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.81
CY2017Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.63
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.66
CY2017Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.13
CY2017Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.78
CY2017Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.61
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.63
CY2017Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.13
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.95
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.96
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.62
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.31
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.92
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.94
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.59
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.29
CY2018	mco	Pension Expense Net Periodic Pension Costs Other PensionExpenseNetPeriodicPensionCostsOther	10300000	USD
CY2017	mco	Pension Expense Net Periodic Pension Costs Other PensionExpenseNetPeriodicPensionCostsOther	8400000	USD
CY2016	mco	Pension Expense Net Periodic Pension Costs Other PensionExpenseNetPeriodicPensionCostsOther	7300000	USD
CY2018	us-gaap	Increase Decrease In Contract With Customer Liability IncreaseDecreaseInContractWithCustomerLiability	138900000	USD
CY2018Q2	dei	Entity Public Float EntityPublicFloat	32700000000	USD
CY2018	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	51100000	USD
CY2017	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	42000000	USD
CY2016	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	40100000	USD
CY2018	us-gaap	Number Of Reporting Units NumberOfReportingUnits	8	pure
CY2018	us-gaap	Concentration Risk Customer ConcentrationRiskCustomer	No customer accounted for 10% or more of accounts receivable at December 31, 2018 or 2017.
CY2018	dei	Entity Small Business EntitySmallBusiness	false
CY2018	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2018	dei	Entity Shell Company EntityShellCompany	false
CY2018	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2018	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2016	us-gaap	Disposal Group Including Discontinued Operation Foreign Currency Translation Gains Losses DisposalGroupIncludingDiscontinuedOperationForeignCurrencyTranslationGainsLosses	36600000	USD
CY2016Q4	us-gaap	Disposal Group Including Discontinued Operation Foreign Currency Translation Gains Losses DisposalGroupIncludingDiscontinuedOperationForeignCurrencyTranslationGainsLosses	35000000	USD
CY2018	us-gaap	Restructuring Charges RestructuringCharges	48700000	USD
CY2018Q4	us-gaap	Restructuring Charges RestructuringCharges	48700000	USD
CY2017	us-gaap	Increase Decrease In Restructuring Reserve IncreaseDecreaseInRestructuringReserve	-5900000	USD
CY2016	us-gaap	Increase Decrease In Restructuring Reserve IncreaseDecreaseInRestructuringReserve	6300000	USD
CY2018	us-gaap	Stock Issued During Period Shares Share Based Compensation Gross StockIssuedDuringPeriodSharesShareBasedCompensationGross	1500000	shares

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$MCO
MOODYS CORP /DE/ Stock $mco

2018 Q4 Form 10-K Financial Statement

#000119312519048576 Filed on February 25, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MCO MOODYS CORP /DE/ Stock $mco

2018 Q4 Form 10-K Financial Statement

#000119312519048576 Filed on February 25, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MCO
MOODYS CORP /DE/ Stock $mco