Finance Receivables and Loans, Net (Allowance for Credit Losses on Financing Receivables) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	$ 3,711	$ 3,267
Charge-offs	(601)	(301)
Recoveries	192	168
Net charge-offs	(409)	(133)
Provision for credit losses	449	167
Other	0	0
Allowance, ending balance	3,751	3,301
Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Provision for credit losses	(3)
Consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-offs	(601)
Consumer | Automotive
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	3,020	2,769
Charge-offs	(536)	(276)
Recoveries	185	163
Net charge-offs	(351)	(113)
Provision for credit losses	353	107
Other	0	0
Allowance, ending balance	3,022	2,763
Consumer | Consumer mortgage
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	27	27
Charge-offs	(1)	(1)
Recoveries	2	3
Net charge-offs	1	2
Provision for credit losses	(4)	(3)
Other	(1)	0
Allowance, ending balance	23	26
Consumer | Consumer other
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	426	221
Charge-offs	(64)	(24)
Recoveries	5	1
Net charge-offs	(59)	(23)
Provision for credit losses	88	59
Other	0	1
Allowance, ending balance	455	258
Fair value, option, carrying amount, financing receivable, no allowance	2	7	$ 3	$ 7
Commercial
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Allowance, beginning balance	238	250
Charge-offs	0	0
Recoveries	0	1
Net charge-offs	0	1
Provision for credit losses	12	4
Other	1	(1)
Allowance, ending balance	$ 251	$ 254