Fair Value Measurements - Total Gains and Losses Included in Earnings for Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Details) - Level 3 - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Gains and losses included in earnings	$ (74)	$ (393)	$ (339)
Mortgage banking net revenue
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Gains and losses included in earnings	9	(291)	(235)
Commercial banking revenue
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Gains and losses included in earnings	3	2	3
Other noninterest income
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Gains and losses included in earnings	$ (86)	$ (104)	$ (107)