Schedule of Notional Amounts of Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2017		Dec. 31, 2016
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 10		$ 24
Energy Related Derivative [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	13		6
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 329	[1]	$ 275

[1] These contracts had maturities of two years or less as of December 31, 2017.