Segment Information (Summary Of Segments Information) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Segment Reporting Information [Line Items]
Revenues	$ 1,881	$ 1,850
Adjusted EBITDA	44	117
Non-vehicle related depreciation and amortization	61	49
Interest expense related to corporate debt, net	50	52
Transaction-related costs, net	4	31
Restructuring expense	15	1
Income before income taxes	(86)	(16)
Americas
Segment Reporting Information [Line Items]
Revenues	1,364	1,375
Adjusted EBITDA	63	115
International
Segment Reporting Information [Line Items]
Revenues	517	475
Adjusted EBITDA	1	16
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Adjusted EBITDA	$ (20)	$ (14)