Finance Receivables and Loans, Net - Schedule of Allowance for Credit Losses on Financing Receivables (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, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	$ 3,398	$ 3,550	$ 3,714	$ 3,587	$ 3,587
Charge-offs	(602)	(676)	(1,347)	(1,434)	(2,948)
Recoveries	236	241	474	460
Net charge-offs	(366)	(435)	(873)	(974)
Write-downs from transfers to held-for-sale				(5)
Provision for credit losses	384	457	575	964
Other	0		0
Allowance, ending balance	3,416	3,572	3,416	3,572	3,714
Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-offs			(1,345)		(2,945)
Consumer | Automotive
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	3,144	3,050	3,170	3,083	3,083
Charge-offs	(599)	(605)	(1,275)	(1,293)	(2,681)
Recoveries	233	227	464	438
Net charge-offs	(366)	(378)	(811)	(855)
Write-downs from transfers to held-for-sale				(5)	(5)
Provision for credit losses	389	383	807	832
Other	(1)		0
Allowance, ending balance	3,166	3,055	3,166	3,055	3,170
Consumer | Consumer mortgage finance receivables
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	18	21	19	21	21
Charge-offs	(2)	0	(2)	(1)	(2)
Recoveries	2	1	3	2
Net charge-offs	0	1	1	1
Write-downs from transfers to held-for-sale				0
Provision for credit losses	(1)	(3)	(1)	(3)
Other	0		(2)
Allowance, ending balance	17	19	17	19	19
Consumer | Other
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance		291	319	293	293
Charge-offs		(70)	(68)	(138)	(262)
Recoveries		8	5	14
Net charge-offs		(62)	(63)	(124)
Write-downs from transfers to held-for-sale				0
Provision for credit losses		73	(257)	133
Other			1
Allowance, ending balance	0	302	0	302	319
Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	236	188	206	190	190
Charge-offs	(1)	(1)	(2)	(2)	(3)
Recoveries	1	5	2	6
Net charge-offs	0	4	0	4
Write-downs from transfers to held-for-sale				0
Provision for credit losses	(4)	4	26	2
Other	1		1
Allowance, ending balance	$ 233	$ 196	233	$ 196	206
Commercial | Automotive
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-offs			$ (2)		$ (3)