Securitizations and Variable Interest Entities (Schedule of Quantitative Information and Net Credit Losses about Securitized and Other Financial Assets Managed Together) (Details) - Off-balance sheet variable interest entities - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Total amount	$ 3,620		$ 2,639
Amount 60 days or more past due	71		72
Net credit losses	32	$ 6
Off-balance-sheet securitization entities | Automotive | Consumer
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Total amount	2,444		1,558
Amount 60 days or more past due	13		11
Net credit losses	4	0
Whole-loan sales | Automotive | Consumer
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Total amount	1,065		956
Amount 60 days or more past due	44		44
Net credit losses	16	1
Whole-loan sales | Consumer other | Consumer
Derecognized Assets, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together [Line Items]
Total amount	111		125
Amount 60 days or more past due	14		$ 17
Net credit losses	$ 12	$ 5