Goodwill (Tables)

12 Months Ended

Dec. 31, 2016

Goodwill And Intangible Assets Disclosure [Abstract]

Summary of Goodwill Identified by Segment

Goodwill is identified by segment as follows (in millions):

	United States			Canada			International			Total
Balance at December 31, 2014	$	220		$	101		$	25		$	346
Additions		173			4			99			276
Impairment		(393	)		—			—			(393	)
Currency translation adjustments and other		—			(17	)		(7	)		(24	)
Balance at December 31, 2015		—			88			117			205
Additions	$	117			—			—			117
Currency translation adjustments and other		—		$	3		$	(14	)		(11	)
Balance at December 31, 2016	$	117		$	91		$	103		$	311