Consolidating Condensed Statements of Operations (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Vehicle rental	$ 6,081,000,000	$ 6,026,000,000	$ 6,026,000,000
Other	2,578,000,000	2,476,000,000	2,459,000,000
Net revenues	8,659,000,000	8,502,000,000	8,485,000,000
Operating	4,382,000,000	4,284,000,000	4,251,000,000
Vehicle depreciation and lease charges, net	2,047,000,000	1,933,000,000	1,996,000,000
Selling, general and administrative	1,134,000,000	1,093,000,000	1,080,000,000
Vehicle interest, net	284,000,000	289,000,000	282,000,000
Non-vehicle related depreciation and amortization	253,000,000	218,000,000	180,000,000
Interest expense	203,000,000	194,000,000	209,000,000
Intercompany interest expense (income)	0	0	0
Early extinguishment of debt	27,000,000	23,000,000	56,000,000
Restructuring expense	29,000,000	18,000,000	26,000,000
Transaction-related costs, net	21,000,000	68,000,000	13,000,000
Total expenses	8,380,000,000	8,120,000,000	8,093,000,000
Income before income taxes	279,000,000	382,000,000	392,000,000
Provision for (benefit from) income taxes	116,000,000	69,000,000	147,000,000
Equity in earnings (loss) of subsidiaries	0	0	0
Net income	163,000,000	313,000,000	245,000,000
Total comprehensive income	156,000,000	188,000,000	106,000,000
Parent Company
Condensed Financial Statements, Captions [Line Items]
Vehicle rental	0	0	0
Other	0	0	0
Net revenues	0	0	0
Operating	4,000,000	2,000,000	10,000,000
Vehicle depreciation and lease charges, net	0	0	0
Selling, general and administrative	38,000,000	32,000,000	27,000,000
Vehicle interest, net	0	0	0
Non-vehicle related depreciation and amortization	0	0	0
Interest expense	0	0	2,000,000
Intercompany interest expense (income)	(13,000,000)	(12,000,000)	(13,000,000)
Early extinguishment of debt	0	0	0
Restructuring expense	0	0	0
Transaction-related costs, net	0	0	1,000,000
Total expenses	29,000,000	22,000,000	27,000,000
Income before income taxes	(29,000,000)	(22,000,000)	(27,000,000)
Provision for (benefit from) income taxes	(11,000,000)	(9,000,000)	(10,000,000)
Equity in earnings (loss) of subsidiaries	181,000,000	326,000,000	262,000,000
Net income	163,000,000	313,000,000	245,000,000
Total comprehensive income	156,000,000	188,000,000	106,000,000
Subsidiary Issuers
Condensed Financial Statements, Captions [Line Items]
Vehicle rental	0	0	0
Other	0	0	0
Net revenues	0	0	0
Operating	18,000,000	17,000,000	13,000,000
Vehicle depreciation and lease charges, net	0	1,000,000	1,000,000
Selling, general and administrative	18,000,000	15,000,000	23,000,000
Vehicle interest, net	0	0	0
Non-vehicle related depreciation and amortization	2,000,000	1,000,000	2,000,000
Interest expense	141,000,000	159,000,000	163,000,000
Intercompany interest expense (income)	(7,000,000)	(11,000,000)	(11,000,000)
Early extinguishment of debt	10,000,000	23,000,000	56,000,000
Restructuring expense	0	0	0
Transaction-related costs, net	2,000,000	22,000,000	8,000,000
Total expenses	184,000,000	227,000,000	255,000,000
Income before income taxes	(184,000,000)	(227,000,000)	(255,000,000)
Provision for (benefit from) income taxes	(70,000,000)	(178,000,000)	(108,000,000)
Equity in earnings (loss) of subsidiaries	295,000,000	375,000,000	409,000,000
Net income	181,000,000	326,000,000	262,000,000
Total comprehensive income	173,000,000	203,000,000	123,000,000
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Vehicle rental	4,134,000,000	4,124,000,000	4,038,000,000
Other	1,209,000,000	1,181,000,000	1,167,000,000
Net revenues	5,343,000,000	5,305,000,000	5,205,000,000
Operating	2,622,000,000	2,587,000,000	2,525,000,000
Vehicle depreciation and lease charges, net	1,993,000,000	1,819,000,000	1,920,000,000
Selling, general and administrative	631,000,000	619,000,000	602,000,000
Vehicle interest, net	198,000,000	204,000,000	200,000,000
Non-vehicle related depreciation and amortization	155,000,000	133,000,000	111,000,000
Interest expense	3,000,000	(5,000,000)	2,000,000
Intercompany interest expense (income)	23,000,000	16,000,000	1,000,000
Early extinguishment of debt	0	0	0
Restructuring expense	9,000,000	6,000,000	7,000,000
Transaction-related costs, net	1,000,000	6,000,000	(20,000,000)
Total expenses	5,635,000,000	5,385,000,000	5,348,000,000
Income before income taxes	(292,000,000)	(80,000,000)	(143,000,000)
Provision for (benefit from) income taxes	123,000,000	170,000,000	186,000,000
Equity in earnings (loss) of subsidiaries	710,000,000	625,000,000	738,000,000
Net income	295,000,000	375,000,000	409,000,000
Total comprehensive income	283,000,000	253,000,000	273,000,000
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Vehicle rental	1,947,000,000	1,902,000,000	1,988,000,000
Other	3,563,000,000	3,335,000,000	3,426,000,000
Net revenues	5,510,000,000	5,237,000,000	5,414,000,000
Operating	1,738,000,000	1,678,000,000	1,703,000,000
Vehicle depreciation and lease charges, net	2,045,000,000	1,936,000,000	1,996,000,000
Selling, general and administrative	447,000,000	427,000,000	428,000,000
Vehicle interest, net	289,000,000	302,000,000	295,000,000
Non-vehicle related depreciation and amortization	96,000,000	84,000,000	67,000,000
Interest expense	59,000,000	40,000,000	42,000,000
Intercompany interest expense (income)	(3,000,000)	7,000,000	23,000,000
Early extinguishment of debt	17,000,000	0	0
Restructuring expense	20,000,000	12,000,000	19,000,000
Transaction-related costs, net	18,000,000	40,000,000	24,000,000
Total expenses	4,726,000,000	4,526,000,000	4,597,000,000
Income before income taxes	784,000,000	711,000,000	817,000,000
Provision for (benefit from) income taxes	74,000,000	86,000,000	79,000,000
Equity in earnings (loss) of subsidiaries	0	0	0
Net income	710,000,000	625,000,000	738,000,000
Total comprehensive income	712,000,000	504,000,000	624,000,000
Eliminations
Condensed Financial Statements, Captions [Line Items]
Vehicle rental	0	0	0
Other	(2,194,000,000)	(2,040,000,000)	(2,134,000,000)
Net revenues	(2,194,000,000)	(2,040,000,000)	(2,134,000,000)
Operating	0	0	0
Vehicle depreciation and lease charges, net	(1,991,000,000)	(1,823,000,000)	(1,921,000,000)
Selling, general and administrative	0	0	0
Vehicle interest, net	(203,000,000)	(217,000,000)	(213,000,000)
Non-vehicle related depreciation and amortization	0	0	0
Interest expense	0	0	0
Intercompany interest expense (income)	0	0	0
Early extinguishment of debt	0	0	0
Restructuring expense	0	0	0
Transaction-related costs, net	0	0	0
Total expenses	(2,194,000,000)	(2,040,000,000)	(2,134,000,000)
Income before income taxes	0	0	0
Provision for (benefit from) income taxes	0	0	0
Equity in earnings (loss) of subsidiaries	(1,186,000,000)	(1,326,000,000)	(1,409,000,000)
Net income	(1,186,000,000)	(1,326,000,000)	(1,409,000,000)
Total comprehensive income	$ (1,168,000,000)	$ (960,000,000)	$ (1,020,000,000)