Summary of Geographic Segment Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 8,502	$ 8,485	$ 7,937
Assets exclusive of assets under vehicle programs	5,918	5,784	5,698
Assets under vehicle programs	11,716	11,058	10,452
Long-Lived Assets	2,571	2,366	2,228
Deferred Finance Costs, Net		127	134
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	5,635	5,471	5,030
Assets exclusive of assets under vehicle programs	3,677	3,745	3,608
Assets under vehicle programs	8,786	8,428	7,791
Long-Lived Assets	1,502	1,481	1,281
Deferred Finance Costs, Net		114	121
All Other Countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	2,867	3,014	2,907
Assets exclusive of assets under vehicle programs	2,241	2,039	2,090
Assets under vehicle programs	2,930	2,630	2,661
Long-Lived Assets	$ 1,069	885	947
Deferred Finance Costs, Net		$ 13	$ 13