Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Jun. 03, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents					$ 5,601	$ 200,050		$ 8,812		$ 3,885	$ 1,521
Deferred tax asset					24,587
Property and equipment, net	$ 1,415,025				3,205,187
Current liabilities:
Asset retirement obligations	38,056	$ 39,831	$ 39,831	$ 39,831	$ 39,831	39,859		51,601
Current maturities of long-term debt	3,364	3,176
Long-term debt, less current maturities of long-term debt	1,014,459	1,017,855	1,020,462	$ 1,023,033	$ 1,025,566
Intercompany promissory note	325,000
Asset retirement obligations	202,306	214,355	218,317	232,419	232,864	220,302		203,849
Deferred tax liabilities					483,810
Successor Company [Member]
Current assets:
Cash and cash equivalents	217	95	484	23	5,601	200,050
Trade accounts receivable - net	71,323	53,992	68,917	67,385	72,301	93,007
Derivative financial instruments	$ 888	2,906	2,004	2,262
Deferred tax asset		16,760	15,748	24,587	24,587	24,587
Restricted cash	$ 6,024
Prepaid expenses	1,831	6,135	10,060	14,345	26,521	9,809
Total current assets	80,283	79,888	97,213	108,602	129,010	327,453
Property and equipment, net	$ 1,415,025	2,072,922	2,547,479	3,262,727	3,205,187	2,941,892
Goodwill					329,293	329,293
Restricted cash		6,024	6,024	6,023	6,023	6,023
Other assets and debt issuance costs, net of accumulated amortization	$ 1,039	1,068	16	143	317	1,175
Total Assets	1,496,347	2,159,902	2,650,732	3,377,657	3,669,830	3,605,863
Current liabilities:
Accounts payable	24,548	30,398	25,326	79,179	92,981	63,996
Due to EGC	170,728	182,792	138,057	29,975	4,960
Accrued expenses	95,981	72,397	133,026	181,754	161,518	230,086
Asset retirement obligations	38,056	39,831	39,831	39,831	39,831	43,617
Fair value of commodity derivative instruments	1,057			1,446	26,440	22,625
Current maturities of long-term debt	3,364	3,176
Total current liabilities	333,734	328,594	336,240	332,185	325,730	360,324
Long-term debt, less current maturities of long-term debt	689,459	692,855	1,020,462	1,023,033	1,025,566	1,026,407
Intercompany promissory note	325,000	325,000
Asset retirement obligations	$ 202,306	214,355	218,317	232,419	232,864	229,755
Deferred tax liabilities		55,985	236,961	496,657	483,810	483,591
Derivative financial instruments					2,140	1,439
Other			6	5	6	6
Total Liabilities	$ 1,550,499	$ 1,616,789	$ 1,811,986	$ 2,084,299	$ 2,070,116	$ 2,101,522
Commitments and contingencies (Note 14)
Stockholders' equity (deficit):
Preferred stock, par value $0.001 per share. Authorized 1,000,000 shares; no shares issued and outstanding
Common stock, par value $0.001 per share
Additional paid-in capital	$ 1,599,341	$ 1,599,341	$ 1,599,341	$ 1,599,341	$ 1,599,341	$ 1,504,341
Retained earnings (accumulated deficit)	(1,653,493)	(1,056,228)	(760,595)	(305,983)	373
Total stockholders' equity (deficit)	(54,152)	543,113	838,746	1,293,358	1,599,714	1,504,341
Total liabilities and stockholders' equity (deficit)	$ 1,496,347	$ 2,159,902	$ 2,650,732	$ 3,377,657	$ 3,669,830	3,605,863
Predecessor Company [Member]
Current assets:
Cash and cash equivalents						200,050	$ 4,448	8,812	$ 2,939	$ 3,885	1,521	$ 80,128
Trade accounts receivable - net						91,813
Deferred tax asset						8,405
Prepaid expenses						9,729
Total current assets						309,997
Property and equipment, net						1,969,382
Restricted cash						6,023
Deferred financing costs - net						9,002
Other assets and debt issuance costs, net of accumulated amortization						1,175
Total Assets						2,295,606
Current liabilities:
Accounts payable						61,938
Accrued expenses						230,086
Asset retirement obligations						39,859
Fair value of commodity derivative instruments						22,625
Total current liabilities						354,508
Long-term debt, less current maturities of long-term debt						973,440
Asset retirement obligations						220,302
Deferred tax liabilities						126,764
Derivative financial instruments						1,439
Other						803
Total Liabilities						$ 1,677,256
Commitments and contingencies (Note 14)
Stockholders' equity (deficit):
Common stock, par value $0.001 per share						$ 41
Additional paid-in capital						538,844
Treasury stock, at cost						(38,794)
Retained earnings (accumulated deficit)						118,259
Total stockholders' equity (deficit)						618,350		$ 629,213			$ 545,973	$ 491,045
Total liabilities and stockholders' equity (deficit)						$ 2,295,606