Segment Information (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Document Period End Date			Jun. 30, 2016
Revenues	$ 2,243	$ 2,173	$ 4,124	$ 4,023
Adjusted EBITDA	204	227	248	344
Non Vehicle Related Depreciation And Amortization	65	56	126	105
Restructuring expense	5	3	20	4
Income (loss) before income taxes	63	82	(23)	66
Assets Under Vehicle Programs	14,023		14,023		$ 11,716
International
Segment Reporting Information [Line Items]
Revenues	650	617	1,167	1,092
Adjusted EBITDA	57	61	58	77
Assets Under Vehicle Programs	3,100		3,100		2,300
Americas
Segment Reporting Information [Line Items]
Revenues	1,593	1,556	2,957	2,931
Adjusted EBITDA	163	178	226	293
Assets Under Vehicle Programs	10,900		10,900		$ 9,400
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Adjusted EBITDA	$ (16)	$ (12)	$ (36)	$ (26)