Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Third-party midstream services revenues	$ 2,099	$ 918	$ 3,654	$ 1,391
Plant and other midstream services operating	2,942	1,061	$ 5,283	2,088
Discount rate present value of future revenue from proved oil and gas reserves			10.00%
Full-cost ceiling impairment	0	78,171	$ 0	158,633
Capitalized general and administrative costs	5,200	4,000	10,800	6,000
Capitalized interest expense	$ 1,900	1,700	$ 3,200	2,200
Reclassification from Other Income to Third-Party Midstream Services Revenue [Member] | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Third-party midstream services revenues		900		1,400
Reclassification from Lease Operating Expenses to Plant and Other Midstream Services Operating Expenses [Member] | Restatement Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Plant and other midstream services operating		$ 1,100		$ 2,100