Derivative Financial Instruments and Risk Management (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Foreign currency cash flow hedges, maximum allowable period (in years)	5 years
Foreign currency cash flow hedges, maximum period (in months)	51 months
Deferred net losses, foreign currency exchange rate risk, to be reclassified from equity to current earnings over the next twelve months	$ 34
Derivative
Commodity forward and option contracts, maximum period (in years)	5 years