Goodwill and Other Intangible Assets - Schedule of Goodwill (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,849
Goodwill acquired during the year (preliminary allocation)	1,629
Goodwill, ending balance	3,478
Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	1,767
Goodwill acquired during the year (preliminary allocation)	1,337
Goodwill, ending balance	3,104
Wealth
Goodwill [Roll Forward]
Goodwill, beginning balance	82
Goodwill acquired during the year (preliminary allocation)	292
Goodwill, ending balance	$ 374

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details