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	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Derivative liabilities, net of derivative assets
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of the period	$ 1	$ 4	$ 0	$ 3
Net realized/unrealized losses (gains)
Included in earnings	1	0	2	(1)
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	2
Fair value at ending of the period	2	4	2	4
Fair Value, Liability, Recurring Basis, Still Held [Abstract]
Included in earnings	2	0	2	0
Included in OCI	0	0	0	0
Hedged available-for-sale securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of the period	34	35	34	35
Net realized/unrealized gains
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Purchases and originations	1	0	1	0
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	(1)	0	(1)	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	34	35	34	35
Fair Value, Asset, Recurring Basis, Still Held [Abstract]
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Loans held-for-sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of the period	0	3	0	5
Net realized/unrealized gains
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Purchases and originations	0	1	0	9
Sales	0	(4)	0	(14)
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	0	0	0
Fair Value, Asset, Recurring Basis, Still Held [Abstract]
Included in earnings	0	0	0	0
Included in OCI	$ 0	$ 0	$ 0	$ 0

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

+ Details

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- Details

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- Details

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