Segment Reporting - Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Total revenue	$ 3,811	$ 3,343
Operating expenses	458	442
Leased vehicle expenses	1,047	1,039
Provision for loan losses	204	131
Interest expense	1,396	1,000
Equity income	32	41
Income before income taxes	737	771
North America
Segment Reporting Information [Line Items]
Total revenue	3,417	3,049
Operating expenses	369	358
Leased vehicle expenses	1,024	1,022
Provision for loan losses	171	114
Interest expense	1,230	877
Equity income	0	0
Income before income taxes	623	677
International
Segment Reporting Information [Line Items]
Total revenue	394	294
Operating expenses	90	84
Leased vehicle expenses	23	17
Provision for loan losses	33	17
Interest expense	167	123
Equity income	32	41
Income before income taxes	$ 114	$ 94