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Segment Information - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) segment lineOfBusiness
Segment Reporting Information [Line Items]
Number of operating segments | segment	2
Number of reportable segments | segment	2
MA
Segment Reporting Information [Line Items]
Number of lines of business | lineOfBusiness	3
MIS
Segment Reporting Information [Line Items]
Number of lines of business | lineOfBusiness	5
Strategic and Operational Efficiency Restructuring Program | MA | Minimum
Segment Reporting Information [Line Items]
Restructuring and related cost, expected cost	$ 125
Strategic and Operational Efficiency Restructuring Program | MA | Maximum
Segment Reporting Information [Line Items]
Restructuring and related cost, expected cost	155
Strategic and Operational Efficiency Restructuring Program | MIS | Minimum
Segment Reporting Information [Line Items]
Restructuring and related cost, expected cost	75
Strategic and Operational Efficiency Restructuring Program | MIS | Maximum
Segment Reporting Information [Line Items]
Restructuring and related cost, expected cost	$ 95

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- Definition

Number of Lines of Businesses

+ References

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
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-Publisher FASB
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-Publisher FASB
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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-Topic 280
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Amount expected to be recognized in earnings for the specified restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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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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