Fair Value (Fair Value Measurements - Reconciliation of Level 3 Assets And Liabilities) (Details) - Fair value, measurements, recurring - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Derivative liabilities, net of derivative assets
Net unrealized gains still held at March 31,
Included in OCI	$ 0	$ 0
Liabilities
Fair value at beginning of the period	8	39
Net realized/unrealized gains
Included in earnings	(4)	0
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	4	3
Fair value at ending of the period	8	42
Net unrealized (gains) losses still held at March 31,
Included in earnings	(2)	3
Included in OCI	0	0
Equity securities
Assets
Fair value at beginning of the period	1	1
Net realized/unrealized gains
Included in earnings	0	0
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	(1)	0
Fair value at ending of the period	0	1
Net unrealized gains still held at March 31,
Included in earnings	0	0
Included in OCI	0	0
Net unrealized (gains) losses still held at March 31,
Included in OCI	0	0
Hedged available-for-sale securities
Assets
Fair value at beginning of the period	9	4
Net realized/unrealized gains
Included in earnings	0	0
Included in OCI	0	0
Purchases	2	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value at ending of the period	11	4
Net unrealized gains still held at March 31,
Included in earnings	0	0
Included in OCI	0	0
Net unrealized (gains) losses still held at March 31,
Included in OCI	0	0
Finance receivables and loans, net \| Consumer Loan
Assets
Fair value at beginning of the period	0	3
Net realized/unrealized gains
Included in earnings	0	0
Included in OCI	0	0
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	(1)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value at ending of the period	0	2
Net unrealized gains still held at March 31,
Included in earnings	0	0
Included in OCI	0	0
Net unrealized (gains) losses still held at March 31,
Included in OCI	$ 0	$ 0

Fair Value, Asset, Recurring Basis, Still Held

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Fair Value, Liability, Recurring Basis, Still Held

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Section 50
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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

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

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Amount of issuances 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 level 3 of the fair value hierarchy.

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

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

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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.

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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.

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