Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Cash paid for income taxes, net of refunds	$ 121	$ 20	$ 34
Cash paid for interest	209	$ 193	$ 201
Non-cash purchase price consideration	$ 89