Fair Value - Schedule of Fair Value Measurements - Reconciliation of Level 3 Assets And Liabilities (Details) - Fair value, measurements, recurring - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Derivative liabilities, net of derivative assets
Liabilities
Fair value at beginning of the period	$ 8	$ 39
Fair value at January 1,
Included in earnings	(18)	(11)
Included in OCI	0	0
Purchases and originations	0	0
Sales	0	0
Issuances	0	0
Settlements	(4)	(34)
Transfers into Level 3	0	0
Transfers out of Level 3	17	14
Fair value at ending of the period	3	8
Net unrealized gains still held at December 31,
Included in earnings	(7)	(7)
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 and originations	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 December 31,
Included in earnings	0	0
Included in OCI	0	0
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 and originations	29	5
Sales	0	0
Issuances	0	0
Settlements	(3)	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value at ending of the period	35	9
Net unrealized gains still held at December 31,
Included in earnings	0	0
Included in OCI	0	0
Available-for-sale debt security	27
Loans held-for-sale
Assets
Fair value at beginning of the period	0	0
Net realized/unrealized gains
Included in earnings	0	0
Included in OCI	0	0
Purchases and originations	31	0
Sales	(26)	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	5	0
Net unrealized gains still held at December 31,
Included in earnings	0	0
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 and originations	0	0
Sales	0	0
Issuances	0	0
Settlements	0	(3)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value at ending of the period	0	0
Net unrealized gains still held at December 31,
Included in earnings	0	0
Included in OCI	$ 0	$ 0

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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