Restructuring (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 10
Norco Restructuring and Related Cost, Accelerated Depreciation	30		$ 76
Loss on Contract Termination	25
Other Liabilities	18		18
Costs Incurred, Asset Retirement Obligation Incurred	30		30
Costs Incurred, Asset Retirement Obligation Incurred	30	$ 6
Norco ARO Liability	$ 10		$ 10