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, 2023	Mar. 31, 2022
Derivative liabilities, net of derivative assets
Net realized/unrealized gains (losses)
Transfers into Level 3	$ 0	$ 0
Transfers out of Level 3	(3)	0
Net unrealized losses still held at March 31,
Included in OCI	0	0
Liabilities
Fair value at beginning of the period	39	53
Net realized/unrealized losses
Included in earnings	0	8
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	3	0
Fair value at ending of the period	42	61
Net unrealized losses still held at March 31,
Included in earnings	3	5
Included in OCI	0	0
Equity securities
Assets
Fair value at beginning of the period	1	9
Net realized/unrealized gains (losses)
Included in earnings	0	1
Included in OCI	0	0
Purchases	0	0
Sales	0	(9)
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	1	1
Net unrealized losses still held at March 31,
Included in earnings	0	0
Included in OCI	0	0
Net realized/unrealized losses
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Net unrealized losses still held at March 31,
Included in OCI	0	0
Available-for-sale securities
Assets
Fair value at beginning of the period	4	9
Net realized/unrealized gains (losses)
Included in earnings	0	0
Included in OCI	0	0
Purchases	0	2
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	4	11
Net unrealized losses still held at March 31,
Included in earnings	0	0
Included in OCI	0	0
Net realized/unrealized losses
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Net unrealized losses still held at March 31,
Included in OCI	0	0
Finance receivables and loans, net
Net realized/unrealized gains (losses)
Purchases	0	4
Finance receivables and loans, net \| Consumer Loan
Assets
Fair value at beginning of the period	3	7
Net realized/unrealized gains (losses)
Included in earnings	0	(1)
Included in OCI	0	0
Sales	0	0
Issuances	0	0
Settlements	(1)	(3)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value at ending of the period	2	7
Net unrealized losses still held at March 31,
Included in earnings	0	(1)
Included in OCI	0	0
Net realized/unrealized losses
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Net unrealized 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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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

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-Topic 820
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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 purchases 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 issuances 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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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.

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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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