Fair Value of Assets and Liabilities - Schedule of Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Level 3 - Recurring - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net derivative liabilities
Beginning balance	$ (18)	$ (18)	$ (25)	$ (15)
Total net gains (losses) included in net income	(5)	0	(5)	(5)
Sales		0		0
Settlements	1	5	8	7
Net transfers into (out of) Level 3	0	0	0	0
Ending balance	(22)	(13)	(22)	(13)
Net unrealized gains (losses) included in net income	(5)	0	(5)	(5)
SBA interest-only strips
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	35	22	45	23
Total net gains (losses) included in net income	(3)	(2)	(5)	(4)
Sales		0		(3)
Settlements	0	0	0	0
Net transfers into (out of) Level 3	2	7	(6)	11
Ending balance	34	27	34	27
Net unrealized gains (losses) included in net income	(1)	(1)	(1)	(2)
Loans held for sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	14	13	14	16
Total net gains (losses) included in net income	0	0	0	0
Sales		(1)		(5)
Settlements	0	0	0	0
Net transfers into (out of) Level 3	0	0	0	1
Ending balance	14	12	14	12
Net unrealized gains (losses) included in net income	$ 0	$ 0	$ 0	$ 0

Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Amount of unrealized gain (loss) recognized in income for derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3) and still held.

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Amount of transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into (out of) level 3 of the fair value hierarchy.

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