Other (Income) Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Other Income and Expenses [Abstract]
Gain (Loss) on Sale and Revaluation of Assets	$ 15	$ 6	$ 30	$ 12
Other - net	2	4	9	(5)
Other (Income) Expense - Net	(13)	(2)	(21)	(17)
Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component	$ (6)	$ (2)	$ (8)	$ (5)