Finance Receivables and Loans, Net (Loan Modifications) (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023 USD ($) loan	Sep. 30, 2023 USD ($) loan
Financing Receivable, Troubled Debt Restructuring
Trial modifications, term		3 months
Trial modifications, amount	$ 4	$ 4
Total	106	$ 269
Percentage of total		0.20%
Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	37	$ 65
Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	63	149
Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	1	13
Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	4	9
Combination
Financing Receivable, Troubled Debt Restructuring
Total	1	33
Consumer
Financing Receivable, Troubled Debt Restructuring
Total	69	157
Consumer | Current
Financing Receivable, Troubled Debt Restructuring
Total	64	134
Consumer | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	3	10
Consumer | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	4
Consumer | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	2	9
Consumer | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	63	102
Consumer | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	1	13
Consumer | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	4	9
Consumer | Combination
Financing Receivable, Troubled Debt Restructuring
Total	1	33
Consumer | Automotive
Financing Receivable, Troubled Debt Restructuring
Total	$ 63	$ 142
Number of loans redefualted | loan	67	108
Amortized cost of loans redefaulted	$ 1	$ 3
Consumer | Automotive | Current
Financing Receivable, Troubled Debt Restructuring
Total	60	125
Consumer | Automotive | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	2	9
Consumer | Automotive | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	3
Consumer | Automotive | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	1	5
Consumer | Automotive | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Number of months extended/deferred	28 months	27 months
Consumer | Automotive | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	$ 62	$ 99
Consumer | Automotive | Contractual maturity extensions | Current
Financing Receivable, Troubled Debt Restructuring
Total	60	89
Consumer | Automotive | Contractual maturity extensions | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	2	7
Consumer | Automotive | Contractual maturity extensions | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	2
Consumer | Automotive | Contractual maturity extensions | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	1
Consumer | Automotive | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	1	13
Principal forgiveness, amount forgiven	0	2
Consumer | Automotive | Principal forgiveness | Current
Financing Receivable, Troubled Debt Restructuring
Total	0	8
Consumer | Automotive | Principal forgiveness | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	1
Consumer | Automotive | Principal forgiveness | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Automotive | Principal forgiveness | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	1	4
Consumer | Automotive | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Consumer | Automotive | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 30
Interest rate concessions, initial rate	0.00%	10.40%
Interest rate concessions, revised rate	0.00%	9.70%
Payment extensions, initial term		75 months
Payment extensions, revised term		85 months
Consumer | Automotive | Combination | Current
Financing Receivable, Troubled Debt Restructuring
Total		$ 28
Consumer | Automotive | Combination | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total		1
Consumer | Automotive | Combination | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total		1
Consumer | Automotive | Combination | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total		0
Consumer | Consumer mortgage
Financing Receivable, Troubled Debt Restructuring
Total	$ 2	$ 6
Number of loans redefualted | loan		1
Amortized cost of loans redefaulted		$ 2
Consumer | Consumer mortgage | Current
Financing Receivable, Troubled Debt Restructuring
Total	2	4
Consumer | Consumer mortgage | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Consumer mortgage | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Consumer mortgage | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	2
Consumer | Consumer mortgage | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Number of months extended/deferred	210 months	149 months
Consumer | Consumer mortgage | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	$ 3
Consumer | Consumer mortgage | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Principal forgiveness, amount forgiven	0	0
Consumer | Consumer mortgage | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Consumer | Consumer mortgage | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	$ 3
Number of months extended/deferred		210 months
Interest rate concessions, initial rate	2.50%	4.30%
Interest rate concessions, revised rate	2.00%	3.10%
Payment extensions, initial term	180 months	284 months
Payment extensions, revised term	280 months	435 months
Consumer | Mortgage Finance
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	$ 4
Consumer | Mortgage Finance | Current
Financing Receivable, Troubled Debt Restructuring
Total	1	2
Consumer | Mortgage Finance | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage Finance | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage Finance | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	2
Consumer | Mortgage Finance | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Number of months extended/deferred	210 months	186 months
Consumer | Mortgage Finance | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	$ 2
Consumer | Mortgage Finance | Contractual maturity extensions | Current
Financing Receivable, Troubled Debt Restructuring
Total	1	2
Consumer | Mortgage Finance | Contractual maturity extensions | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage Finance | Contractual maturity extensions | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage Finance | Contractual maturity extensions | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage Finance | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Principal forgiveness, amount forgiven	0	0
Consumer | Mortgage Finance | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Consumer | Mortgage Finance | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 2
Interest rate concessions, initial rate	0.00%	4.60%
Interest rate concessions, revised rate	0.00%	3.40%
Payment extensions, initial term		309 months
Payment extensions, revised term		470 months
Consumer | Mortgage Finance | Combination | Current
Financing Receivable, Troubled Debt Restructuring
Total		$ 0
Consumer | Mortgage Finance | Combination | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total		0
Consumer | Mortgage Finance | Combination | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total		0
Consumer | Mortgage Finance | Combination | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total		2
Consumer | Mortgage — Legacy
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	2
Consumer | Mortgage — Legacy | Current
Financing Receivable, Troubled Debt Restructuring
Total	1	2
Consumer | Mortgage — Legacy | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage — Legacy | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage — Legacy | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage — Legacy | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	0	$ 0
Number of months extended/deferred		76 months
Consumer | Mortgage — Legacy | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	0	$ 1
Consumer | Mortgage — Legacy | Contractual maturity extensions | Current
Financing Receivable, Troubled Debt Restructuring
Total		1
Consumer | Mortgage — Legacy | Contractual maturity extensions | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total		0
Consumer | Mortgage — Legacy | Contractual maturity extensions | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total		0
Consumer | Mortgage — Legacy | Contractual maturity extensions | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total		0
Consumer | Mortgage — Legacy | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Principal forgiveness, amount forgiven	0	0
Consumer | Mortgage — Legacy | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Consumer | Mortgage — Legacy | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	$ 1
Interest rate concessions, initial rate	2.50%	2.70%
Interest rate concessions, revised rate	2.00%	2.00%
Payment extensions, initial term	180 months	174 months
Payment extensions, revised term	280 months	283 months
Consumer | Mortgage — Legacy | Combination | Current
Financing Receivable, Troubled Debt Restructuring
Total	$ 1	$ 1
Consumer | Mortgage — Legacy | Combination | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage — Legacy | Combination | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Mortgage — Legacy | Combination | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Other
Financing Receivable, Troubled Debt Restructuring
Total	4	9
Consumer | Other | Current
Financing Receivable, Troubled Debt Restructuring
Total	2	5
Consumer | Other | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	1	1
Consumer | Other | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	1
Consumer | Other | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	1	2
Consumer | Other | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Other | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Other | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Principal forgiveness, amount forgiven	0	0
Consumer | Other | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 4	$ 9
Interest rate concessions, initial rate	30.00%	30.00%
Interest rate concessions, revised rate	11.00%	8.00%
Consumer | Other | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Consumer | Credit Card
Financing Receivable, Troubled Debt Restructuring
Total	$ 4	$ 9
Consumer | Credit Card | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Credit Card | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Consumer | Credit Card | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Principal forgiveness, amount forgiven	0	0
Consumer | Credit Card | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 4	$ 9
Interest rate concessions, initial rate	30.00%	30.00%
Interest rate concessions, revised rate	11.00%	8.00%
Consumer | Credit Card | Interest rate concessions | Current
Financing Receivable, Troubled Debt Restructuring
Total	$ 2	$ 5
Consumer | Credit Card | Interest rate concessions | 30–59 days past due
Financing Receivable, Troubled Debt Restructuring
Total	1	1
Consumer | Credit Card | Interest rate concessions | 60–89 days past due
Financing Receivable, Troubled Debt Restructuring
Total	0	1
Consumer | Credit Card | Interest rate concessions | 90 or more days past due
Financing Receivable, Troubled Debt Restructuring
Total	1	2
Consumer | Credit Card | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Commercial
Financing Receivable, Troubled Debt Restructuring
Total	$ 37	$ 112
Commercial | Pass
Financing Receivable, Troubled Debt Restructuring
Total	0	34
Commercial | Special mention
Financing Receivable, Troubled Debt Restructuring
Total	0	7
Commercial | Substandard
Financing Receivable, Troubled Debt Restructuring
Total	0	6
Commercial | Doubtful
Financing Receivable, Troubled Debt Restructuring
Total	37	65
Commercial | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	$ 37	$ 65
Number of months extended/deferred	3 months	13 months
Commercial | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 47
Commercial | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Principal forgiveness, amount forgiven	0	0
Commercial | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Commercial | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Commercial | Other
Financing Receivable, Troubled Debt Restructuring
Total	$ 37	$ 112
Commercial | Other | Payment deferrals
Financing Receivable, Troubled Debt Restructuring
Total	$ 37	$ 65
Number of months extended/deferred	3 months	13 months
Commercial | Other | Payment deferrals | Pass
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Commercial | Other | Payment deferrals | Special mention
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Commercial | Other | Payment deferrals | Substandard
Financing Receivable, Troubled Debt Restructuring
Total	0	0
Commercial | Other | Payment deferrals | Doubtful
Financing Receivable, Troubled Debt Restructuring
Total	37	65
Commercial | Other | Contractual maturity extensions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 47
Commercial | Other | Contractual maturity extensions | Corporate Finance operations
Financing Receivable, Troubled Debt Restructuring
Number of months extended/deferred	3 months	3 months
Commercial | Other | Contractual maturity extensions | Pass
Financing Receivable, Troubled Debt Restructuring
Total		$ 34
Commercial | Other | Contractual maturity extensions | Special mention
Financing Receivable, Troubled Debt Restructuring
Total		7
Commercial | Other | Contractual maturity extensions | Substandard
Financing Receivable, Troubled Debt Restructuring
Total		6
Commercial | Other | Contractual maturity extensions | Doubtful
Financing Receivable, Troubled Debt Restructuring
Total		0
Commercial | Other | Principal forgiveness
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	0
Principal forgiveness, amount forgiven	0	0
Commercial | Other | Interest rate concessions
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%
Commercial | Other | Combination
Financing Receivable, Troubled Debt Restructuring
Total	$ 0	$ 0
Interest rate concessions, initial rate	0.00%	0.00%
Interest rate concessions, revised rate	0.00%	0.00%