Fair Value Measurement - Nonrecurring Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 394	$ 347
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	0	0
Loans held for sale	426	515
Other investments	1,330	1,329
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	306,948	308,044
Loans held for sale	0	0
Other investments	0	0
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	514	545
Loans held for sale	10	37
Other assets	101	214
Total	625	796
Nonrecurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	0	0
Loans held for sale	10	37
Other assets	0	0
Total	10	37
Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	514	545
Loans held for sale	0	0
Other assets	101	214
Total	615	759
Equity investments accounted for under measurement alternative	47	46
Foreclosed property and repossessed assets, fair value disclosure	$ 54	45
Long lived assets held for sale		$ 123