Schedule Of Debt Under Vehicle Programs (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Interest rate on capital leases	1.16%	1.25%
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	$ 6,400
Debt under vehicle programs	6,857	$ 11,068
Debt Due To Rental Car Funding [Member]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	8,000
Debt under vehicle programs	5,116	7,975
Deferred Finance Costs, Net	$ (35)	$ (36)
Americas Debt Borrowings [Member]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Debt, Weighted Average Interest Rate	2.98%	2.87%
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	$ 900
Debt under vehicle programs	$ 509	$ 827
International Debt Borrowings
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Debt, Weighted Average Interest Rate	2.17%	1.87%
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	$ 2,300
Debt under vehicle programs	1,115	$ 2,100
International Capital Leases
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	200
Debt under vehicle programs	162	215
Debt Under Vehicle Programs [Member]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Debt under vehicle programs	6,902
Deferred Finance Costs, Net	$ (45)	$ (49)