Finance Receivables and Loans, Net - Schedule of Financing Receivable Gross Charge-Offs (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	$ 160	$ 239
Year two, originated, current fiscal year, writeoff	779	1,034
Year three, originated, current fiscal year, writeoff	943	680
Year four, originated, current fiscal year, writeoff	511	197
Year five, originated, current fiscal year, writeoff	137	221
More than five years before current fiscal year, writeoff	154	151
Revolving loans	248	188
Revolving loans converted to term	16	10
Total	2,948	2,720
Write-downs from transfers to held-for-sale	5	215
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	160	239
Year two, originated, current fiscal year, writeoff	779	1,034
Year three, originated, current fiscal year, writeoff	943	680
Year four, originated, current fiscal year, writeoff	511	197
Year five, originated, current fiscal year, writeoff	137	142
More than five years before current fiscal year, writeoff	153	123
Revolving loans	246	165
Revolving loans converted to term	16	10
Total	2,945	2,590
Consumer \| Automotive
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	160	225
Year two, originated, current fiscal year, writeoff	779	952
Year three, originated, current fiscal year, writeoff	943	651
Year four, originated, current fiscal year, writeoff	510	194
Year five, originated, current fiscal year, writeoff	137	142
More than five years before current fiscal year, writeoff	152	120
Revolving loans	0	0
Revolving loans converted to term	0	0
Total	2,681	2,284
Write-downs from transfers to held-for-sale	5	41
Consumer \| Consumer mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	0	0
Year two, originated, current fiscal year, writeoff	0	0
Year three, originated, current fiscal year, writeoff	0	0
Year four, originated, current fiscal year, writeoff	1	0
Year five, originated, current fiscal year, writeoff	0	0
More than five years before current fiscal year, writeoff	1	3
Revolving loans	0	0
Revolving loans converted to term	0	0
Total	2	3
Write-downs from transfers to held-for-sale	0	0
Consumer \| Other
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	0	14
Year two, originated, current fiscal year, writeoff	0	82
Year three, originated, current fiscal year, writeoff	0	29
Year four, originated, current fiscal year, writeoff	0	3
Year five, originated, current fiscal year, writeoff	0	0
More than five years before current fiscal year, writeoff	0	0
Revolving loans	246	165
Revolving loans converted to term	16	10
Total	262	303
Write-downs from transfers to held-for-sale	0	174
Consumer \| Personal Lending
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff		14
Year two, originated, current fiscal year, writeoff		82
Year three, originated, current fiscal year, writeoff		29
Year four, originated, current fiscal year, writeoff		3
Year five, originated, current fiscal year, writeoff		0
More than five years before current fiscal year, writeoff		0
Revolving loans		0
Revolving loans converted to term		0
Total		128
Consumer \| Credit Card
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	0	0
Year two, originated, current fiscal year, writeoff	0	0
Year three, originated, current fiscal year, writeoff	0	0
Year four, originated, current fiscal year, writeoff	0	0
Year five, originated, current fiscal year, writeoff	0	0
More than five years before current fiscal year, writeoff	0	0
Revolving loans	246	165
Revolving loans converted to term	16	10
Total	262	175
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	0	0
Year two, originated, current fiscal year, writeoff	0	0
Year three, originated, current fiscal year, writeoff	0	0
Year four, originated, current fiscal year, writeoff	0	0
Year five, originated, current fiscal year, writeoff	0	79
More than five years before current fiscal year, writeoff	1	28
Revolving loans	2	23
Revolving loans converted to term	0	0
Total	3	130
Write-downs from transfers to held-for-sale	0	0
Commercial \| Automotive
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	0	0
Year two, originated, current fiscal year, writeoff	0	0
Year three, originated, current fiscal year, writeoff	0	0
Year four, originated, current fiscal year, writeoff	0	0
Year five, originated, current fiscal year, writeoff	0	0
More than five years before current fiscal year, writeoff	1	5
Revolving loans	2	19
Revolving loans converted to term	0	0
Total	$ 3	24
Commercial \| Other
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff		0
Year two, originated, current fiscal year, writeoff		0
Year three, originated, current fiscal year, writeoff		0
Year four, originated, current fiscal year, writeoff		0
Year five, originated, current fiscal year, writeoff		79
More than five years before current fiscal year, writeoff		23
Revolving loans		4
Revolving loans converted to term		0
Total		$ 106

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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