Reportable Segments (Segment Information) (Details) - USD ($) $ in Thousands		2 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 05, 2015	Feb. 28, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Operating Revenues
Natural gas sales			$ 4,434	$ 5,730	$ 8,709	$ 15,946
Oil sales			2,159	19,501	4,746	25,104
Natural gas liquid sales			264	394	784	1,280
Gathering and transportation sales			12,997		41,130
Total revenues			19,854	25,625	55,369	42,330
Operating expenses:
Lease operating expenses			2,767	5,194	11,918	15,452
Transportation operating expenses			3,111		9,179
Cost of sales			99	139	292	469
Production taxes			290	443	837	1,396
General and administrative			6,286	7,301	16,983	18,206
Unit compensation expense			90	75	1,619	2,463
(Gain) loss on sale of assets			219	2	219	(111)
Depreciation, depletion and amortization			7,507	2,851	20,824	9,050
Asset impairments	$ 0	$ 0		937	1,309	84,664
Accretion expense			271	265	901	782	$ 1,099
Total operating expenses			20,640	17,207	64,081	132,371
Operating income (loss)			(786)	8,418	(8,712)	(90,041)
Upstream
Operating Revenues
Natural gas sales			4,434	5,730	8,709	15,946
Oil sales			2,159	19,501	4,746	25,104
Natural gas liquid sales			264	394	784	1,280
Total revenues			6,857	25,625	14,239	42,330
Operating expenses:
Lease operating expenses			2,651	5,194	11,430	15,452
Cost of sales			99	139	292	469
Production taxes			290	443	837	1,396
General and administrative			4,778	7,301	12,762	18,206
Unit compensation expense			90	75	1,619	2,463
(Gain) loss on sale of assets			219	2	219	(111)
Depreciation, depletion and amortization			2,411	2,851	5,560	9,050
Asset impairments				937	1,309	84,664
Accretion expense			207	265	714	782
Total operating expenses			10,745	17,207	34,742	132,371
Operating income (loss)			(3,888)	$ 8,418	(20,503)	$ (90,041)
Midstream
Operating Revenues
Gathering and transportation sales			12,997		41,130
Total revenues			12,997		41,130
Operating expenses:
Lease operating expenses			116		488
Transportation operating expenses			3,111		9,179
General and administrative			1,508		4,221
Depreciation, depletion and amortization			5,096		15,264
Accretion expense			64		187
Total operating expenses			9,895		29,339
Operating income (loss)			$ 3,102		$ 11,791