Fair Value Measurement - Nonrecurring Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale	$ 206	$ 755
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	58	5
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	444,126	438,783
Loans held for sale	0	0
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	473	662
Loans held for sale	0	5
Other assets	99	131
Total	572	798
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	0	5
Other assets	0	0
Total	0	5
Nonrecurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	473	662
Loans held for sale	0	0
Other assets	99	131
Total	572	793
Equity investments accounted for under measurement alternative	17	44
Foreclosed property and repossessed assets, fair value disclosure	$ 82	82
Long lived assets held for sale		$ 5

Foreclosed property and repossessed assets, fair value disclosure

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Fair value portion of asset recognized for present right to economic benefit.

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Fair value portion of assets classified as held for sale.

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Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of other assets.

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