Fair Value - Schedule of Fair Value Measurements - Reconciliation of Level 3 Assets And Liabilities (Details) - Fair value, measurements, recurring - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Derivative liabilities, net of derivative assets
Liabilities
Fair value at beginning of the period	$ 4	$ 3	$ 3	$ 8
Net realized/unrealized gains
Included in earnings	0	(5)	(1)	(14)
Included in OCI	0	0	0	0
Purchases and originations	0	0	0	0
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	(4)	0	(4)	(5)
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	5	2	14
Fair value at ending of the period	0	3	0	3
Net unrealized gains still held at September 30,
Included in earnings	0	(2)	0	(7)
Included in OCI	0	0	0	0
Equity securities
Assets
Fair value at beginning of the period	0	0	0	1
Net realized/unrealized gains
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Purchases and originations	0	0	0	0
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	(1)
Fair value at ending of the period	0	0	0	0
Net unrealized gains still held at September 30,
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Available-for-sale securities
Assets
Fair value at beginning of the period	35	11	35	9
Net realized/unrealized gains
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Purchases and originations	0	27	0	29
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Fair value at ending of the period	35	38	35	38
Net unrealized gains still held at September 30,
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Available-for-sale debt security		27		27
Loans held-for-sale
Assets
Fair value at beginning of the period	0	2	5	0
Net realized/unrealized gains
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Purchases and originations	0	16	9	18
Sales	0	(11)	(14)	(11)
Issuances	0	0	0	0
Settlements	0	0	0	0
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	0	0	0	0
Fair value at ending of the period	0	7	0	7
Net unrealized gains still held at September 30,
Included in earnings	0	0	0	0
Included in OCI	$ 0	$ 0	$ 0	$ 0

Fair Value, Asset, Recurring Basis, Still Held

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