Derivative Financial Instruments - Schedule of Location and Fair Value Amounts of All Derivative Instruments (Details) - Derivatives Not Designated as Hedging Contracts [Member] - Commodity Contracts [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current Derivative Assets [Member]
Derivatives Fair Value [Line Items]
Gross Recognized Assets	$ 3,626	$ 3,569
Net Recognized Assets	3,626	$ 3,569
Noncurrent Derivative Assets [Member]
Derivatives Fair Value [Line Items]
Gross Recognized Assets	287
Net Recognized Assets	$ 287