Derivative Financial Instruments - Net Gain (Loss) Recognized in Income on Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative [Line Items]
Derivative gain (loss)	$ 153	$ 19	$ 57	$ (32)
Futures | Net return on mortgage servicing rights
Derivative [Line Items]
Derivative gain (loss)	(12)	0	(7)	0
Interest rate swaps and swaptions | Net return on mortgage servicing rights
Derivative [Line Items]
Derivative gain (loss)	124	(3)	76	(30)
Mortgage-backed securities forwards | Net return on mortgage servicing rights
Derivative [Line Items]
Derivative gain (loss)	99	(1)	60	(12)
Rate lock commitments and MSR forwards | Net gain on loan sales
Derivative [Line Items]
Derivative gain (loss)	(60)	23	(73)	8
Forward commitments | Other noninterest income
Derivative [Line Items]
Derivative gain (loss)	8	0	5	0
Interest rate swaps | Other noninterest income
Derivative [Line Items]
Derivative gain (loss)	$ (6)	$ 0	$ (4)	$ 2