Summary of Segments Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net revenues	$ 8,659	$ 8,502	$ 8,485
Vehicle depreciation and lease charges, net	2,047	1,933	1,996
Vehicle interest, net	(284)	(289)	(282)
Adjusted EBITDA	838	903	876
Non-vehicle depreciation and amortization	253	218	180
Assets exclusive of assets under vehicle programs	6,065	5,918	5,784
Assets under vehicle programs	11,578	11,716	11,058
Capital expenditures (excluding vehicles)	190	199	182
Americas
Segment Reporting Information [Line Items]
Net revenues	6,121	6,069	5,961
Vehicle depreciation and lease charges, net	1,559	1,478	1,492
Vehicle interest, net	(226)	(234)	(234)
Adjusted EBITDA	633	682	656
Non-vehicle depreciation and amortization	165	143	122
Assets exclusive of assets under vehicle programs	4,017	3,940	3,946
Assets under vehicle programs	9,210	9,440	9,162
Capital expenditures (excluding vehicles)	121	131	113
International
Segment Reporting Information [Line Items]
Net revenues	2,538	2,433	2,524
Vehicle depreciation and lease charges, net	488	455	504
Vehicle interest, net	(58)	(55)	(48)
Adjusted EBITDA	273	277	280
Non-vehicle depreciation and amortization	88	75	58
Assets exclusive of assets under vehicle programs	1,990	1,901	1,730
Assets under vehicle programs	2,368	2,276	1,896
Capital expenditures (excluding vehicles)	62	68	69
Corporate and Other
Segment Reporting Information [Line Items]
Adjusted EBITDA	(68)	(56)	(60)
Assets exclusive of assets under vehicle programs	58	77	108
Capital expenditures (excluding vehicles)	7
Acquisition-related Costs [Member]
Segment Reporting Information [Line Items]
Non-vehicle depreciation and amortization	$ 59	$ 55	$ 33