Segment Information (Summary Of Segments Information) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Revenues	$ 3,547	$ 3,001	$ 9,223	$ 6,744
Adjusted EBITDA	1,460	1,057	3,475	1,728
Non-vehicle related depreciation and amortization	61	69	174	204
Less:
Interest expense	64	47	181	167
Early extinguishment of debt	0	7	0	136
Restructuring and other related charges	2	5	16	47
Unprecedented personal-injury and other legal matters, net	0	5	1	(6)
Transaction-related costs, net	0	1	1	3
COVID-19 charges	0	(6)	(9)	12
Other (income) expense, net	(9)	0	(9)	0
Net income	1,342	929	3,120	1,165
Minimum annual guaranteed rent in excess of concession fees, net	0	(4)	(9)	12
Vehicles damaged in overflow parking lots, net of insurance proceeds	0	(3)	0	(7)
Other charges	0	1	0	7
COVID-19 charges	0	(6)	(9)	12
Statements of Operations | Cloud Based Computing Costs
Less:
COVID-19 charges	2		6	5
COVID-19 charges	2		6	5
Operating Expense
Less:
COVID-19 charges	0	(6)	(9)	11
COVID-19 charges	0	(6)	(9)	11
Selling, general and administrative expenses
Less:
COVID-19 charges			0	1
COVID-19 charges			0	1
COVID-19 Charges
Less:
COVID-19 charges	0	(6)	(9)	12
COVID-19 charges	0	(6)	(9)	12
Corporate and Other
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Adjusted EBITDA	(16)	(23)	(58)	(52)
Americas | Geographical
Segment Reporting Information [Line Items]
Revenues	2,703	2,403	7,270	5,457
Adjusted EBITDA	1,185	952	3,036	1,694
International | Geographical
Segment Reporting Information [Line Items]
Revenues	844	598	1,953	1,287
Adjusted EBITDA	$ 291	$ 128	$ 497	$ 86