Derivative Instruments and Hedging Activities - Effect of Derivative Instruments on the Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Effect of derivative instruments on the Consolidated Balance Sheet
Derivative Assets	$ 1,662	$ 0
Derivative Liabilities	6,153	0
Other current assets | Derivatives Not Designated as Hedges | Commodity contracts
Effect of derivative instruments on the Consolidated Balance Sheet
Derivative Assets	518	0
Derivative Liabilities	0	0
Other assets (non-current) | Derivatives Not Designated as Hedges | Commodity contracts
Effect of derivative instruments on the Consolidated Balance Sheet
Derivative Assets	1,144	0
Derivative Liabilities	0	0
Derivative instruments (current) | Derivatives Not Designated as Hedges | Commodity contracts
Effect of derivative instruments on the Consolidated Balance Sheet
Derivative Assets	0	0
Derivative Liabilities	5,818	0
Other liabilities (non-current) | Derivatives Not Designated as Hedges | Commodity contracts
Effect of derivative instruments on the Consolidated Balance Sheet
Derivative Assets	0	0
Derivative Liabilities	$ 335	$ 0