Accelerated Share Repurchases, Total Value Committed to Repurchase

No definition available.

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Namespace Prefix:	mco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Final price paid per share for the purchase of the targeted number of shares, determined by an average market price over a fixed period of time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- 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

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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Accelerated Share Repurchase Program - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions			12 Months Ended
	Apr. 26, 2019	Feb. 20, 2019	Dec. 31, 2021
Accelerated Share Repurchases [Line Items]
Accelerated share repurchases, final price paid per share (in usd per share)			$ 180.33
Accelerated Share Repurchases
Accelerated Share Repurchases [Line Items]
Treasury stock, shares, acquired (in shares)			2.8
February 20, 2019
Accelerated Share Repurchases [Line Items]
Accelerated share repurchases, total Value committed to repurchase		$ 500,000,000
Accelerated share repurchases payment		$ 500,000,000
February 20, 2019 \| Accelerated Share Repurchases
Accelerated Share Repurchases [Line Items]
Treasury stock, shares, acquired (in shares)		2.2
April 26, 2019 \| Accelerated Share Repurchases
Accelerated Share Repurchases [Line Items]
Treasury stock, shares, acquired (in shares)	0.6