Segment Information (Summary of Segments Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Revenues	$ 2,551	$ 2,557
Adjusted EBITDA	12	535
Reconciliation of Adjusted EBITDA to income (loss) before income taxes:
Non-vehicle related depreciation and amortization	61	56
Interest expense related to corporate debt, net	83	73
Restructuring and other related charges	3	4
Transaction-related costs, net	1	0
Other (income) expense, net	1	(2)
Legal matters, net	(5)	0
Income (loss) before income taxes	(142)	397
Operating Expense | Cloud Computing Costs
Reconciliation of Adjusted EBITDA to income (loss) before income taxes:
Cloud computing costs	10	7
Corporate and Other
Segment Reporting Information [Line Items]
Revenues	0	0
Adjusted EBITDA	(17)	(31)
Americas | Geographical
Segment Reporting Information [Line Items]
Revenues	1,993	2,016
Adjusted EBITDA	44	516
International | Geographical
Segment Reporting Information [Line Items]
Revenues	558	541
Adjusted EBITDA	$ (15)	$ 50