Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Commodity Derivatives - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	$ 13,863	$ 36,083
Liabilities	(1,150)
Total	12,713	36,083
Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets	13,863	36,083
Liabilities	(1,150)
Total	$ 12,713	$ 36,083