Unrecognized Tax Benefits, Period Increase (Decrease), Net of Federal Tax

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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- Definition

A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Effective tax rate (percent)	24.00%	19.90%	23.50%	14.60%
Excess tax benefits from stock compensation			$ 23
Unrecognized tax benefits, period increase (decrease), net of federal tax	$ 2		$ 13
Income tax examination, description			Moody’s is subject to U.S. federal income tax as well as income tax in various state, local and foreign jurisdictions. The tax years 2021 through 2023 remain open to examination. The Company’s New York City tax returns for 2018 through 2022 are currently under examination. The Company’s U.K. tax returns for 2017 through 2022 remain open to examination.
Foreign Tax Jurisdiction
Effective Income Tax Rate Reconciliation [Line Items]
Effective income tax rate reconciliation, change in enacted tax rate, amount			$ 7