Other Income, Net Table (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Income and Expenses [Abstract]
Interest income	$ 2	$ 1	$ 3	$ 1
Components of net periodic benefit cost other than service cost (Note 9)	(2)	(4)	(3)	(7)
Other, net	4	3	10	0
Other income (expense), net	$ 4	$ 0	$ 10	$ (6)