Segment Information (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) segment	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of segments | segment			2
Oil and natural gas revenues	$ 113,764,000	$ 69,336,000	$ 228,611,000	$ 113,262,000
Third-party midstream services revenues	2,099,000	918,000	3,654,000	1,391,000
Realized gain (loss) on derivatives	558,000	2,465,000	(1,661,000)	9,528,000
Unrealized gain (loss) on derivatives	13,190,000	(26,625,000)	33,821,000	(33,464,000)
Expenses	90,622,000	146,705,000	171,157,000	292,957,000
Operating Income (Loss)	38,989,000	(100,611,000)	93,268,000	(202,240,000)
Total assets	1,777,076,000	1,086,088,000	1,777,076,000	1,086,088,000	$ 1,464,665,000
Capital Expenditures	194,682,000	110,829,000	417,399,000	197,948,000
Depreciation, Depletion and Amortization	41,274,000	31,248,000	75,266,000	60,170,000
Net income attributable to non-controlling interest in subsidiaries	3,178,000	106,000	5,094,000	93,000
Impairment of Oil and Gas Properties	0	78,171,000	0	158,633,000
Corporate [Member]
Segment Reporting Information [Line Items]
Oil and natural gas revenues		0	0	0
Third-party midstream services revenues	0	0	0	0
Realized gain (loss) on derivatives		0	0	0
Unrealized gain (loss) on derivatives		0	0	0
Expenses	15,852,000	13,356,000	31,608,000	26,665,000
Operating Income (Loss)	(15,852,000)	(13,356,000)	(31,608,000)	(26,665,000)
Total assets	147,509,000	52,106,000	147,509,000	52,106,000
Capital Expenditures	1,752,000	2,328,000	3,216,000	3,582,000
Depreciation, Depletion and Amortization	400,000	200,000	700,000	300,000
Eliminations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas revenues		0	0	0
Third-party midstream services revenues	(9,268,000)	(2,551,000)	(17,329,000)	(4,169,000)
Realized gain (loss) on derivatives		0	0	0
Unrealized gain (loss) on derivatives		0	0	0
Expenses	(9,268,000)	(2,551,000)	(17,329,000)	(4,169,000)
Total assets	0	0	0	0
Capital Expenditures	0	0	0	0
Exploration and Production Segment [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Oil and natural gas revenues	113,387,000	68,864,000	227,552,000	112,672,000
Third-party midstream services revenues	0	0	0	0
Realized gain (loss) on derivatives	558,000	2,465,000	(1,661,000)	9,528,000
Unrealized gain (loss) on derivatives	13,190,000	(26,625,000)	33,821,000	(33,464,000)
Expenses	78,078,000	134,338,000	146,416,000	267,365,000
Operating Income (Loss)	49,057,000	(89,634,000)	113,296,000	(178,629,000)
Total assets	1,436,678,000	927,557,000	1,436,678,000	927,557,000
Capital Expenditures	165,583,000	97,309,000	373,956,000	162,116,000
Depreciation, Depletion and Amortization	39,600,000	30,600,000	72,100,000	58,900,000
Impairment of Oil and Gas Properties		78,200,000		158,600,000
Midstream Segment [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Oil and natural gas revenues	377,000	472,000	1,059,000	590,000
Third-party midstream services revenues	11,367,000	3,469,000	20,983,000	5,560,000
Realized gain (loss) on derivatives		0	0	0
Unrealized gain (loss) on derivatives		0	0	0
Expenses	5,960,000	1,562,000	10,462,000	3,096,000
Operating Income (Loss)	5,784,000	2,379,000	11,580,000	3,054,000
Total assets	192,889,000	106,425,000	192,889,000	106,425,000
Capital Expenditures	27,347,000	11,192,000	40,227,000	32,250,000
Depreciation, Depletion and Amortization	1,300,000	500,000	2,500,000	1,000,000
Net income attributable to non-controlling interest in subsidiaries		$ 106,000	5,100,000	$ 93,000
Payments to Acquire Productive Assets, Noncontrolling Interest	13,400,000		$ 18,600,000
Operating Income (Loss) [Member] | Midstream Segment [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net income attributable to non-controlling interest in subsidiaries	$ 3,200,000