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, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff			$ 13		$ 239
Year two, originated, current fiscal year, writeoff			362		1,034
Year three, originated, current fiscal year, writeoff			486		680
Year four, originated, current fiscal year, writeoff			273		197
Year five, originated, current fiscal year, writeoff			74		221
More than five years before current fiscal year, writeoff			87		151
Revolving loans			131		188
Revolving loans converted to term			8		10
Total	$ 676	$ 629	1,434	$ 1,230	2,720
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		239
Year two, originated, current fiscal year, writeoff			362		1,034
Year three, originated, current fiscal year, writeoff			486		680
Year four, originated, current fiscal year, writeoff			273		197
Year five, originated, current fiscal year, writeoff			74		142
More than five years before current fiscal year, writeoff			86		123
Revolving loans			130		165
Revolving loans converted to term			8		10
Total			1,432		2,590
Consumer | Automotive
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, originated, current fiscal year, writeoff			13		225
Year two, originated, current fiscal year, writeoff			362		952
Year three, originated, current fiscal year, writeoff			486		651
Year four, originated, current fiscal year, writeoff			272		194
Year five, originated, current fiscal year, writeoff			74		142
More than five years before current fiscal year, writeoff			86		120
Revolving loans			0		0
Revolving loans converted to term			0		0
Total	605	496	1,293	1,032	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			0		3
Revolving loans			0		0
Revolving loans converted to term			0		0
Total	0	2	1	3	3
Write-downs from transfers to held-for-sale			0
Consumer | Mortgage Finance
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			0		1
Revolving loans			0		0
Revolving loans converted to term			0		0
Total			1		1
Consumer | Mortgage — Legacy
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					0
More than five years before current fiscal year, writeoff					2
Revolving loans					0
Revolving loans converted to term					0
Total					2
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			130		165
Revolving loans converted to term			8		10
Total	70	70	138	134	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			130		165
Revolving loans converted to term			8		10
Total			138		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			1		23
Revolving loans converted to term			0		0
Total	$ 1	$ 61	2	$ 61	130
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			1		5
Revolving loans			1		19
Revolving loans converted to term			0		0
Total			$ 2		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