Goodwill and Mortgage Servicing Rights - by Business Segment and Corporate (Details) - USD ($) $ in Millions	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Goodwill [Line Items]
Total goodwill	$ 52,492	$ 52,380	$ 51,662	$ 51,461	$ 50,697	$ 50,315
Corporate
Goodwill [Line Items]
Total goodwill	655		646
Consumer & Community Banking | Operating Segments
Goodwill [Line Items]
Total goodwill	32,116		32,121
Corporate & Investment Bank | Operating Segments
Goodwill [Line Items]
Total goodwill	8,244		8,008
Commercial Banking | Operating Segments
Goodwill [Line Items]
Total goodwill	2,985		2,985
Asset & Wealth Management | Operating Segments
Goodwill [Line Items]
Total goodwill	$ 8,492		$ 7,902