Goodwill and Other Intangible Assets - Schedule of Goodwill (Details) $ in Millions	6 Months Ended
Jun. 30, 2026 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,849
Goodwill acquired during the year (preliminary allocation)	1,630
Goodwill, ending balance	3,479
Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	1,767
Goodwill acquired during the year (preliminary allocation)	1,338
Goodwill, ending balance	3,105
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