Schedule of Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Gross goodwill			$ 2,960
Goodwill [Roll Forward]
Goodwill	$ 973	$ 842
Goodwill, Impaired, Accumulated Impairment Loss			(2,118)
Acquisition	25	194
Adjustments to the allocation of purchase price	9	(63)
Goodwill	1,007	973
Americas
Goodwill [Line Items]
Gross goodwill			2,066
Goodwill [Roll Forward]
Goodwill	537	479
Goodwill, Impaired, Accumulated Impairment Loss			1,587
Acquisition	2	77
Adjustments to the allocation of purchase price	13	(19)
Goodwill	552	537
International
Goodwill [Line Items]
Gross goodwill			894
Goodwill [Roll Forward]
Goodwill	436	363
Goodwill, Impaired, Accumulated Impairment Loss			$ 531
Acquisition	23	117
Adjustments to the allocation of purchase price	(4)	(44)
Goodwill	$ 455	$ 436