Goodwill, Mortgage Servicing Rights, and Other Intangible Assets - Goodwill by Business Segment and Corporate (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022
Goodwill [Line Items]
Total goodwill	$ 52,711	$ 52,620	$ 52,634	$ 52,492	$ 52,380	$ 51,662
Corporate
Goodwill [Line Items]
Total goodwill	740		685
Consumer & Community Banking | Operating Segments
Goodwill [Line Items]
Total goodwill	32,116		32,116
Commercial & Investment Bank | Operating Segments
Goodwill [Line Items]
Total goodwill	11,259		11,251
Asset & Wealth Management | Operating Segments
Goodwill [Line Items]
Total goodwill	$ 8,596		$ 8,582