Finance Receivables and Loans, Net - Schedule of Troubled Debt Restructurings (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) loan	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Financing Receivable, Troubled Debt Restructuring
Financing receivable, modifications, gross carrying value	$ 2,400
Loans modified, commitment to lend	$ 61	$ 39	$ 6
Number of loans | loan	52,662
Pre-modification amortized cost basis	$ 1,310
Post-modification amortized cost basis	$ 1,289
Consumer
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	52,657
Pre-modification amortized cost basis	$ 849
Post-modification amortized cost basis	$ 823
Consumer | Automotive
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	49,773
Pre-modification amortized cost basis	$ 831
Post-modification amortized cost basis	$ 805
Consumer | Consumer mortgage
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	31
Pre-modification amortized cost basis	$ 13
Post-modification amortized cost basis	$ 13
Consumer | Other
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	2,853
Pre-modification amortized cost basis	$ 5
Post-modification amortized cost basis	$ 5
Consumer | Credit Card
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	2,853
Pre-modification amortized cost basis	$ 5
Post-modification amortized cost basis	$ 5
Commercial
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	5
Pre-modification amortized cost basis	$ 461
Post-modification amortized cost basis	$ 466
Commercial | Other
Financing Receivable, Troubled Debt Restructuring
Number of loans | loan	5
Pre-modification amortized cost basis	$ 461
Post-modification amortized cost basis	$ 466