Charges related to the Company's decision to outsource the production of certain sustainability content utilized in our product offerings, including both charges related to severance and accelerated amortization

No definition available.

+ Details

Name:	mco_ChargesRelatedToAssetAbandonment
Namespace Prefix:	mco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- 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 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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Namespace Prefix:
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- Details

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Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense related to property and equipment	$ 233	$ 175	$ 131
Charges related to asset abandonment	43	0	0
Accelerated Amortization Charges
Property, Plant and Equipment [Line Items]
Charges related to asset abandonment	31
Internal-use Computer Software
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense related to property and equipment	180	$ 121	$ 79
Internal-use Computer Software \| Accelerated Amortization Charges
Property, Plant and Equipment [Line Items]
Charges related to asset abandonment	$ 26
Internal-use Computer Software \| Weighted Average
Property, Plant and Equipment [Line Items]
Property plant and equipment useful life	4 years 4 months 24 days