Goodwill And Other Acquired Intangible Assets - Activity in Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Goodwill [Roll Forward]
Beginning balance, goodwill gross	$ 6,006	$ 5,968
Beginning balance, accumulated impairment charge	(12)	(12)
Beginning balance, goodwill net	5,994	5,956
Additions/adjustments	143	209
Foreign currency translation adjustments	329	(171)
Divestiture of business	(9)
Ending balance, goodwill gross	6,380	6,006
Ending balance, accumulated impairment charge	(12)	(12)
Ending balance, goodwill net	6,368	5,994
Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill [Roll Forward]
Reclassification to assets held-for-sale	(89)
MA
Goodwill [Roll Forward]
Beginning balance, goodwill gross	5,626	5,681
Beginning balance, accumulated impairment charge	(12)	(12)
Beginning balance, goodwill net	5,614	5,669
Additions/adjustments	135	112
Foreign currency translation adjustments	334	(167)
Divestiture of business	(9)
Ending balance, goodwill gross	5,997	5,626
Ending balance, accumulated impairment charge	(12)	(12)
Ending balance, goodwill net	5,985	5,614
MA | Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill [Roll Forward]
Reclassification to assets held-for-sale	(89)
MIS
Goodwill [Roll Forward]
Beginning balance, goodwill gross	380	287
Beginning balance, accumulated impairment charge	0	0
Beginning balance, goodwill net	380	287
Additions/adjustments	8	97
Foreign currency translation adjustments	(5)	(4)
Divestiture of business	0
Ending balance, goodwill gross	383	380
Ending balance, accumulated impairment charge	0	0
Ending balance, goodwill net	383	$ 380
MIS | Disposal Group, Held-for-sale, Not Discontinued Operations
Goodwill [Roll Forward]
Reclassification to assets held-for-sale	$ 0