XML 129 R67.htm IDEA: XBRL DOCUMENT
v3.25.1

Derivative Instruments And Hedging Activities - Summary of Notional Amounts of Outstanding Cross Currency Swap (Detail) - Net Investment Hedging € in Millions, $ in Millions, $ in Millions | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Mar. 31, 2025 EUR (€) | Mar. 31, 2025 HKD ($) | Dec. 31, 2024 EUR (€)
Currency Paid | Cross currency swaps | Fixed Pay Weighted Average Interest Rate |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional Amount | € |  |  | € 1,817 |  | € 965
Weighted Average Interest Rate | 2.35% | 2.91% | 2.35% | 2.35% | 2.91%
Currency Paid | Cross currency swaps | Based on ESTR |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional Amount | € |  |  | € 1,688 |  | € 2,138
Floating Interest Rate | Based on ESTR | Based on ESTR |  |  |
Currency Paid | Currency Swap Two | Fixed Pay Weighted Average Interest Rate |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional Amount |  |  |  | $ 1,949 |
Currency Received | Cross currency swaps | Fixed Received Weighted Average Interest Rate |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional Amount | $ 1,914 | $ 1,014 |  |  |
Weighted Average Interest Rate | 3.88% | 4.41% | 3.88% | 3.88% | 4.41%
Currency Received | Cross currency swaps | Based on SOFR |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional Amount | $ 1,750 | $ 2,250 |  |  |
Floating Interest Rate | Based on SOFR | Based on SOFR |  |  |
Currency Received | Currency Swap Two | Fixed Received Weighted Average Interest Rate |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Notional Amount | $ 250 |  |  |  |
Weighted Average Interest Rate | 0.51% |  | 0.51% | 0.51% |

X
- Definition Average variable interest rate related to the group of interest rate derivatives. + References No definition available. + Details
Name: | us-gaap_DerivativeAverageVariableInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480237/815-40-50-5 + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition General discussion of the entity's interest rate fair value hedge activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2 -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-1 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-5 + Details
Name: | us-gaap_DescriptionOfInterestRateFairValueHedgeActivities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_TransactionTypeAxis=mco_CurrencyPaidMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CurrencySwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_NetInvestmentHedgingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mco_FixedRateAxis=mco_FixedPayWeightedAverageInterestRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=mco_EuroShortTermRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=mco_CurrencySwapTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TransactionTypeAxis=mco_CurrencyReceivedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | mco_FixedRateAxis=mco_FixedReceivedWeightedAverageInterestRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |