Derivative Instruments and Hedging Activities - Summary of Location and Fair Value (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Total derivative assets	$ 83	$ 865
Total derivative liabilities	(1,023)	(1,143)
Other Current Assets [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Other current assets: Gain positions	203	1,013
Other current assets: Loss positions	(120)	(148)
Other Current Assets [Member] | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Other current assets: Loss positions	0	0
Other Current Liabilities [Member] | Commodity Contracts [Member]
Derivatives, Fair Value [Line Items]
Other current liability: Gain positions	796	564
Other current liability: Loss positions	(1,770)	(920)
Other Current Liabilities [Member] | Interest Rate Swap [Member]
Derivatives, Fair Value [Line Items]
Other current liability: Loss positions	$ (49)	$ (787)