Fair Value Measurement - Nonrecurring Fair Value Measurements (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 1,000	$ 596
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans held for investment	0	0
Loans held for sale	5,091	2,214
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans held for investment	270,508	244,701
Loans held for sale	0	0
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans held for investment	194	305
Loans held for sale	118
Other assets	325	175
Total assets	637	480
Nonrecurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans held for investment	0	0
Loans held for sale	118
Other assets	0	0
Total assets	118	0
Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans held for investment	194	305
Loans held for sale	0
Other assets	325	175
Total assets	519	480
Equity investments subject to Impairment	50
Equity investments accounted for under measurement alternative	29	25
Foreclosed property and repossessed assets, fair value disclosure	40	42
Long lived assets held for sale	$ 206	$ 108