Segment Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of segments | segment			2
Oil and natural gas revenues	$ 134,948,000	$ 83,079,000	$ 363,559,000	$ 196,341,000
Third-party midstream services revenues	3,218,000	1,566,000	6,871,000	2,956,000
Realized gain (loss) on derivatives	485,000	885,000	(1,176,000)	10,413,000
Unrealized (loss) gain on derivatives	(12,372,000)	3,203,000	21,449,000	(30,261,000)
Expenses	99,730,000	71,879,000	270,887,000	364,835,000
Operating Income (Loss)	26,549,000	16,854,000	119,816,000	(185,386,000)
Total assets	1,848,537,000	1,177,693,000	1,848,537,000	1,177,693,000	$ 1,464,665,000
Capital Expenditures	217,188,000	135,552,000	634,587,000	333,501,000
Depreciation, Depletion and Amortization	47,800,000	30,015,000	123,066,000	90,185,000
Net income attributable to non-controlling interest in subsidiaries	2,940,000	116,000	8,034,000	209,000
Impairment charges	0	0	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 (loss) gain on derivatives		0	0	0
Expenses	15,447,000	13,423,000	47,055,000	40,089,000
Operating Income (Loss)	(15,447,000)	(13,423,000)	(47,055,000)	(40,089,000)
Total assets	35,586,000	32,892,000	35,586,000	32,892,000
Capital Expenditures	1,494,000	1,903,000	4,710,000	5,485,000
Depreciation, Depletion and Amortization	400,000	300,000	1,100,000	600,000
Eliminations [Member]
Segment Reporting Information [Line Items]
Oil and natural gas revenues		0	0	0
Third-party midstream services revenues	(8,043,000)	(4,043,000)	(25,373,000)	(8,212,000)
Realized gain (loss) on derivatives		0	0	0
Unrealized (loss) gain on derivatives		0	0	0
Expenses	(8,043,000)	(4,043,000)	(25,373,000)	(8,212,000)
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	134,488,000	82,794,000	362,040,000	195,467,000
Third-party midstream services revenues	0	0	0	0
Realized gain (loss) on derivatives	485,000	885,000	(1,176,000)	10,413,000
Unrealized (loss) gain on derivatives	(12,372,000)	3,203,000	21,449,000	(30,261,000)
Expenses	86,728,000	60,222,000	233,145,000	327,585,000
Operating Income (Loss)	35,873,000	26,660,000	149,168,000	(151,966,000)
Total assets	1,590,677,000	1,020,648,000	1,590,677,000	1,020,648,000
Capital Expenditures	180,686,000	116,279,000	554,642,000	278,396,000
Depreciation, Depletion and Amortization	46,100,000	28,900,000	118,200,000	87,900,000
Impairment charges				158,600,000
Midstream Segment [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Oil and natural gas revenues	460,000	285,000	1,519,000	874,000
Third-party midstream services revenues	11,261,000	5,609,000	32,244,000	11,168,000
Realized gain (loss) on derivatives		0	0	0
Unrealized (loss) gain on derivatives		0	0	0
Expenses	5,598,000	2,277,000	16,060,000	5,373,000
Operating Income (Loss)	6,123,000	3,617,000	17,703,000	6,669,000
Total assets	222,274,000	124,153,000	222,274,000	124,153,000
Capital Expenditures	35,008,000	17,370,000	75,235,000	49,620,000
Depreciation, Depletion and Amortization	1,300,000	800,000	3,800,000	1,700,000
Net income attributable to non-controlling interest in subsidiaries		$ 116,000	8,000,000	$ 209,000
Payments to Acquire Productive Assets, Noncontrolling Interest	17,200,000		$ 35,800,000
Operating Income (Loss) [Member] | Midstream Segment [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net income attributable to non-controlling interest in subsidiaries	$ 2,900,000