Finance Receivables and Loans, Net (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) loan	Dec. 31, 2022 USD ($)
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, gross carrying value		$ 2,400
Financing receivable, modifications, number of loans \| loan	13,813
Financing receivable, modifications, pre-modification amortized cost basis	$ 272
Financing receivable, modifications, post-modification amortized cost basis	$ 268
Consumer
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	13,812
Financing receivable, modifications, pre-modification amortized cost basis	$ 238
Financing receivable, modifications, post-modification amortized cost basis	$ 234
Consumer \| Automotive
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	13,451
Financing receivable, modifications, pre-modification amortized cost basis	$ 231
Financing receivable, modifications, post-modification amortized cost basis	$ 227
Consumer \| Consumer mortgage
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	10
Financing receivable, modifications, pre-modification amortized cost basis	$ 6
Financing receivable, modifications, post-modification amortized cost basis	$ 6
Consumer \| Mortgage Finance
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	6
Financing receivable, modifications, pre-modification amortized cost basis	$ 5
Financing receivable, modifications, post-modification amortized cost basis	$ 5
Consumer \| Mortgage - Legacy
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	4
Financing receivable, modifications, pre-modification amortized cost basis	$ 1
Financing receivable, modifications, post-modification amortized cost basis	$ 1
Consumer \| Other
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	351
Financing receivable, modifications, pre-modification amortized cost basis	$ 1
Financing receivable, modifications, post-modification amortized cost basis	$ 1
Consumer \| Credit card receivables
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	351
Financing receivable, modifications, pre-modification amortized cost basis	$ 1
Financing receivable, modifications, post-modification amortized cost basis	$ 1
Commercial
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	1
Financing receivable, modifications, pre-modification amortized cost basis	$ 34
Financing receivable, modifications, post-modification amortized cost basis	$ 34
Commercial \| Other
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, number of loans \| loan	1
Financing receivable, modifications, pre-modification amortized cost basis	$ 34
Financing receivable, modifications, post-modification amortized cost basis	$ 34

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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