Finance Receivables and Loans, Net - Schedule of Financing Receivable Gross Charge-Offs (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	$ 1		$ 160
Year two, originated, current fiscal year, writeoff	120		779
Year three, originated, current fiscal year, writeoff	206		943
Year four, originated, current fiscal year, writeoff	200		511
Year five, originated, current fiscal year, writeoff	98		137
More than five years before current fiscal year, writeoff	51		154
Revolving loans	65		248
Revolving loans converted to term	4		16
Total	745	$ 758	2,948
Write-downs from transfers to held-for-sale		5
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	1		160
Year two, originated, current fiscal year, writeoff	120		779
Year three, originated, current fiscal year, writeoff	206		943
Year four, originated, current fiscal year, writeoff	200		511
Year five, originated, current fiscal year, writeoff	98		137
More than five years before current fiscal year, writeoff	51		153
Revolving loans	64		246
Revolving loans converted to term	4		16
Total	744		2,945
Consumer \| Automotive
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff	1		160
Year two, originated, current fiscal year, writeoff	120		779
Year three, originated, current fiscal year, writeoff	206		943
Year four, originated, current fiscal year, writeoff	200		510
Year five, originated, current fiscal year, writeoff	98		137
More than five years before current fiscal year, writeoff	51		152
Revolving loans	0		0
Revolving loans converted to term	0		0
Total	676	688	2,681
Write-downs from transfers to held-for-sale		5	5
Consumer \| Consumer mortgage finance receivables
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			1
Year five, originated, current fiscal year, writeoff			0
More than five years before current fiscal year, writeoff			1
Revolving loans			0
Revolving loans converted to term			0
Total	0	1	2
Write-downs from transfers to held-for-sale		0
Consumer \| Other
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	64		246
Revolving loans converted to term	4		16
Total	68	68	262
Write-downs from transfers to held-for-sale		0
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		0
More than five years before current fiscal year, writeoff	0		1
Revolving loans	1		2
Revolving loans converted to term	0		0
Total	1	1	3
Write-downs from transfers to held-for-sale		$ 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	0		1
Revolving loans	1		2
Revolving loans converted to term	0		0
Total	$ 1		$ 3

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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Amount, excluding accrued interest, of reversal of credit loss expense on financing receivable transferred out of held-for-investment into held-for-sale classification. Excludes net investment in lease.

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