Loans - Consumer, Excluding Credit Card Loan Portfolio, Residential Real Estate, Active and Suspended Foreclosure (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Financing Receivable, Past Due [Line Items]
Carrying value	$ 1,285,370	$ 1,280,870	$ 1,265,941
Consumer, excluding credit card
Financing Receivable, Past Due [Line Items]
Carrying value	377,938	397,275	$ 397,054
Consumer, excluding credit card | Residential real estate
Financing Receivable, Past Due [Line Items]
Carrying value	311,338	326,409
Consumer, excluding credit card | Residential real estate | In process of active or suspended foreclosure
Financing Receivable, Past Due [Line Items]
Carrying value	$ 618	$ 566