Goodwill And Other Acquired Intangible Assets - Activity in Goodwill (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Goodwill [Roll Forward]
Beginning balance, goodwill gross	$ 6,011	$ 4,568
Beginning balance, Accumulated impairment charge	(12)	(12)
Beginning balance, goodwill net	5,999	4,556
Additions/ adjustments	107	1,615
Foreign currency translation adjustments	(67)	(172)
Ending balance, goodwill gross	6,051	6,011
Ending balance, Accumulated impairment charge	(12)	(12)
Ending balance, goodwill net	6,039	5,999
MIS
Goodwill [Roll Forward]
Beginning balance, goodwill gross	396	311
Beginning balance, Accumulated impairment charge	0	0
Beginning balance, goodwill net	396	311
Additions/ adjustments	0	90
Foreign currency translation adjustments	(1)	(5)
Ending balance, goodwill gross	395	396
Ending balance, Accumulated impairment charge	0	0
Ending balance, goodwill net	395	396
MA
Goodwill [Roll Forward]
Beginning balance, goodwill gross	5,615	4,257
Beginning balance, Accumulated impairment charge	(12)	(12)
Beginning balance, goodwill net	5,603	4,245
Additions/ adjustments	107	1,525
Foreign currency translation adjustments	(66)	(167)
Ending balance, goodwill gross	5,656	5,615
Ending balance, Accumulated impairment charge	(12)	(12)
Ending balance, goodwill net	$ 5,644	$ 5,603

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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