Leases - Schedule of Revenues Disaggregated by Geography (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Lessor, Lease, Description [Line Items]
Total lease revenues	$ 2,484	$ 2,385
Operating lease, lease income, statement of income or comprehensive income [extensible enumeration]	Revenues	Revenues
Avis
Lessor, Lease, Description [Line Items]
Total lease revenues	$ 1,400	$ 1,345
Budget
Lessor, Lease, Description [Line Items]
Total lease revenues	940	874
Other
Lessor, Lease, Description [Line Items]
Total lease revenues	144	166
Americas
Lessor, Lease, Description [Line Items]
Total lease revenues	1,941	1,885
Europe, Middle East and Africa
Lessor, Lease, Description [Line Items]
Total lease revenues	355	342
Asia and Australasia
Lessor, Lease, Description [Line Items]
Total lease revenues	$ 188	$ 158