Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Consolidated Statement of Comprehensive Income [Abstract]
Net income	$ 72	$ 60	$ 188	$ 168
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax	51	1	373	(31)
Other comprehensive income (loss)	51	1	373	(31)
Comprehensive income	$ 123	$ 61	$ 561	$ 137