Finance Receivables and Loans, Net - Schedule of Financing Receivable Gross Charge-Offs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff			$ 13		$ 160
Year two, originated, fiscal year before current fiscal year, writeoff			254		779
Year three, originated, two years before current fiscal year, writeoff			383		943
Year four, originated, three years before current fiscal year, writeoff			362		511
Year five, originated, four years before current fiscal year, writeoff			176		137
More than five years before current fiscal year, writeoff			90		154
Revolving loans			65		248
Revolving loans converted to term			4		16
Total	$ 602	$ 676	1,347	$ 1,434	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			13		160
Year two, originated, fiscal year before current fiscal year, writeoff			254		779
Year three, originated, two years before current fiscal year, writeoff			383		943
Year four, originated, three years before current fiscal year, writeoff			362		511
Year five, originated, four years before current fiscal year, writeoff			175		137
More than five years before current fiscal year, writeoff			90		153
Revolving loans			64		246
Revolving loans converted to term			4		16
Total			1,345		2,945
Consumer | Automotive
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff			13		160
Year two, originated, fiscal year before current fiscal year, writeoff			254		779
Year three, originated, two years before current fiscal year, writeoff			383		943
Year four, originated, three years before current fiscal year, writeoff			361		510
Year five, originated, four years before current fiscal year, writeoff			174		137
More than five years before current fiscal year, writeoff			90		152
Revolving loans			0		0
Revolving loans converted to term			0		0
Total	599	605	1,275	1,293	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		0
Year two, originated, fiscal year before current fiscal year, writeoff			0		0
Year three, originated, two years before current fiscal year, writeoff			0		0
Year four, originated, three years before current fiscal year, writeoff			1		1
Year five, originated, four years before current fiscal year, writeoff			1		0
More than five years before current fiscal year, writeoff			0		1
Revolving loans			0		0
Revolving loans converted to term			0		0
Total	2	0	2	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, fiscal year before current fiscal year, writeoff			0		0
Year three, originated, two years before current fiscal year, writeoff			0		0
Year four, originated, three years before current fiscal year, writeoff			0		0
Year five, originated, four years before 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		70	68	138	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, fiscal year before current fiscal year, writeoff			0		0
Year three, originated, two years before current fiscal year, writeoff			0		0
Year four, originated, three years before current fiscal year, writeoff			0		0
Year five, originated, four years before current fiscal year, writeoff			1		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	2	2	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, fiscal year before current fiscal year, writeoff			0		0
Year three, originated, two years before current fiscal year, writeoff			0		0
Year four, originated, three years before current fiscal year, writeoff			0		0
Year five, originated, four years before current fiscal year, writeoff			1		0
More than five years before current fiscal year, writeoff			0		1
Revolving loans			1		2
Revolving loans converted to term			0		0
Total			$ 2		$ 3