Fair Value (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, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative liabilities, net of derivative assets
Net unrealized losses still held at June 30,
Included in OCI	$ 0	$ 0	$ 0	$ 0
Liabilities
Fair value at beginning of the period	42	61	39	53
Net realized/unrealized (gains) losses
Included in earnings	(3)	(1)	(3)	7
Included in OCI	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	(25)	(10)	(25)	(10)
Transfers into Level 3	0	0	0	0
Transfers out of Level 3	4	0	7	0
Fair value at ending of the period	18	50	18	50
Net unrealized gains still held at June 30,
Included in earnings	(1)	(1)	(1)	(4)
Included in OCI	0	0	0	0
Equity securities
Assets
Fair value at beginning of the period	1	1	1	9
Net realized/unrealized gains (losses)
Included in earnings	0	1	0	2
Included in OCI	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	(9)
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	1	2	1	2
Net unrealized losses still held at June 30,
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Net unrealized gains still held at June 30,
Included in OCI	0	0	0	0
Available-for-sale securities
Assets
Fair value at beginning of the period	4	11	4	9
Net realized/unrealized gains (losses)
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Purchases	1	1	1	3
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	5	12	5	12
Net unrealized losses still held at June 30,
Included in earnings	0	0	0	0
Included in OCI	0	0	0	0
Net unrealized gains still held at June 30,
Included in OCI	0	0	0	0
Finance receivables and loans, net \| Consumer Loan
Assets
Fair value at beginning of the period	2	7	3	7
Net realized/unrealized gains (losses)
Included in earnings	0	0	0	(1)
Included in OCI	0	0	0	0
Purchases	0	4	0	8
Sales	0	0	0	0
Issuances	0	0	0	0
Settlements	(2)	(4)	(3)	(7)
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 losses still held at June 30,
Included in earnings	0	0	0	(1)
Included in OCI	0	0	0	0
Net unrealized gains still held at June 30,
Included in OCI	$ 0	$ 0	$ 0	$ 0

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

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