Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Leases [Abstract]
Rent Expense, Net	$ 80	$ 76	$ 76
Leases, Future Minimum Payments Due, Next Twelve Months	66
Leases, Future Minimum Payments, Due in Two Years	60
Operating Leases, Future Minimum Payments, Due in Three Years	42
Leases, Future Minimum Payments, Due in Four Years	34
Leases, Future Minimum Payments, Due in Five Years	25
Leases, Future Minimum Payments, Due Thereafter	64
Leases, Future Minimum Payments Due	291
Purchase Obligations, Future Minimum Payments Due, Current	321
Purchase Obligations, Future Minimum Payments, Due in Two Years	52
Purchase Obligations, Future Minimum Payments, Due in Three Years	39
Purchase Obligations, Future Minimum Payments, Due in Four Years	19
Purchase Obligations, Future Minimum Payments, Due in Five Years	12
Purchase Obligations, Future Minimum Payments, Due Thereafter	15
Purchase Obligations, Future Minimum Payments Due	$ 458