Gulfport Energy (GPOR) 10-Q 7 May 15 2015 Q1 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	3 Months Ended
	Mar. 31, 2015	1-May-15
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Entity Registrant Name	GULFPORT ENERGY CORP
Entity Central Index Key	874499
Current Fiscal Year End Date	-19
Document Fiscal Year Focus	2015
Entity Filer Category	Large Accelerated Filer
Document Fiscal Period Focus	Q1
Entity Common Stock, Shares Outstanding		96,656,652

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$74,740	$142,340
Accounts receivable—oil and gas	79,680	103,858
Accounts receivable—related parties	33	46
Prepaid expenses and other current assets	15,777	3,714
Short-term derivative instruments	93,030	78,391
Total current assets	263,260	328,349
Property and equipment:
Oil and natural gas properties, full-cost accounting, $1,546,804 and $1,465,538 excluded from amortization in 2015 and 2014, respectively	4,177,962	3,923,154
Other property and equipment	19,051	18,344
Accumulated depletion, depreciation, amortization and impairment	-1,140,168	-1,050,879
Property and equipment, net	3,056,845	2,890,619
Other assets:
Equity investments	374,971	369,581
Derivative instruments	41,956	24,448
Other assets	18,566	19,396
Total other assets	435,493	413,425
Total assets	3,755,598	3,632,393
Current liabilities:
Accounts payable and accrued liabilities	400,096	371,410
Asset retirement obligation—current	75	75
Deferred tax liability	29,622	27,070
Short-term derivative instruments	823
Current maturities of long-term debt	1,781	168
Total current liabilities	432,397	398,723
Asset retirement obligation—long-term	18,656	17,863
Deferred tax liability	215,122	203,195
Long-term debt, net of current maturities	779,130	716,316
Total liabilities	1,445,305	1,336,097
Commitments and contingencies (Note 8)
Preferred stock, $.01 par value; 5,000,000 authorized, 30,000 authorized as redeemable 12% cumulative preferred stock, Series A; 0 issued and outstanding	0	0
Stockholders’ equity:
Common stock - $.01 par value, 200,000,000 authorized, 85,715,819 issued and outstanding in 2015 and 85,655,438 in 2014	857	856
Paid-in capital	1,832,063	1,828,602
Accumulated other comprehensive loss	-41,659	-26,675
Retained earnings	519,032	493,513
Total stockholders’ equity	2,310,293	2,296,296
Total liabilities and stockholders’ equity	$3,755,598	$3,632,393

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	3 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Capitalized costs of oil and natural gas properties excluded from amortization	$1,546,804	$1,465,538
Preferred stock, par value (usd per share)	$0.01	$0.01
Preferred stock, shares authorized (shares)	5,000,000	5,000,000
Temporary Equity, Shares Authorized (shares)	30,000	30,000
Preferred stock dividend rate	12.00%	12.00%
Preferred stock Series A, issued (shares)	0	0
Preferred stock Series A, outstanding (shares)	0	0
Common stock, par value (usd per share)	$0.01	$0.01
Common Stock, Shares Authorized (shares)	200,000,000	200,000,000
Common Stock, Shares, Issued (shares)	85,715,819	85,655,438
Common Stock, Shares, Outstanding (shares)	85,715,819	85,655,438

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues:
Gas sales	$118,570	$18,349
Oil and condensate sales	35,500	73,377
Natural gas liquid sales	22,007	26,136
Other income	240	167
Total revenues	176,317	118,029
Costs and expenses:
Lease operating expenses	16,980	11,629
Production taxes	4,285	6,957
Midstream gathering and processing	25,381	7,769
Depreciation, depletion and amortization	89,909	56,877
General and administrative	10,799	9,511
Accretion expense	190	188
Gain on sale of assets	0	-11
Total costs and expenses	147,544	92,920
INCOME FROM OPERATIONS	28,773	25,109
OTHER (INCOME) EXPENSE:
Interest expense	8,759	3,885
Interest income	-9	-106
Litigation settlement	0	18,000
Income from equity method investments	-19,975	-128,475
Total Other (Income) Expense	-11,225	-106,696
INCOME BEFORE INCOME TAXES	39,998	131,805
INCOME TAX EXPENSE	14,479	49,247
NET INCOME	$25,519	$82,558
NET INCOME PER COMMON SHARE:
Basic net income per share (in usd per share)	$0.30	$0.97
Diluted net income per share (in usd per share)	$0.30	$0.96
Weighted average common shares outstanding - Basic (shares)	85,679,606	85,259,407
Weighted average common shares outstanding-Diluted (shares)	86,120,030	85,738,626

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$25,519	$82,558
Foreign currency translation adjustment	-14,984	-7,278
Other comprehensive loss	-14,984	-7,278
Comprehensive income	$10,535	$75,280

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (USD $)	Total	Common Stock [Member]	Paid-In Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]
In Thousands, except Share data, unless otherwise specified
Beginning Balance at Dec. 31, 2013	$2,050,238	$851	$1,813,058	($9,781)	$246,110
Beginning Balance (in shares) at Dec. 31, 2013		85,177,532
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	82,558				82,558
Other Comprehensive Loss	-7,278			-7,278
Stock Compensation	4,307		4,307
Issuance of Restricted Stock (in shares)		63,951
Issuance of Restricted Stock	0	0	0
Issuance of Common Stock through exercise of options (in shares)		182,908
Issuance of Common Stock through exercise of options	615	2	613
Ending Balance at Mar. 31, 2014	2,130,440	853	1,817,978	-17,059	328,668
Ending Balance (in shares) at Mar. 31, 2014		85,424,391
Beginning Balance at Dec. 31, 2014	2,296,296	856	1,828,602	-26,675	493,513
Beginning Balance (in shares) at Dec. 31, 2014	85,655,438	85,655,438
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	25,519				25,519
Other Comprehensive Loss	-14,984			-14,984
Stock Compensation	3,462		3,462
Issuance of Restricted Stock (in shares)		60,381
Issuance of Restricted Stock	0	1	-1
Issuance of Common Stock through exercise of options (in shares)	0	0
Issuance of Common Stock through exercise of options	0	0	0
Ending Balance at Mar. 31, 2015	$2,310,293	$857	$1,832,063	($41,659)	$519,032
Ending Balance (in shares) at Mar. 31, 2015	85,715,819	85,715,819

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$25,519	$82,558
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion of discount—Asset Retirement Obligation	190	188
Depletion, depreciation and amortization	89,909	56,877
Stock-based compensation expense	2,077	2,584
Gain from equity investments	-12,759	-43,688
Interest income - note receivable		-13
Unrealized (gain) loss on derivative instruments	-31,324	8,665
Deferred income tax expense	14,479	33,564
Amortization of loan commitment fees	617	294
Amortization of note discount and premium	-528	78
Changes in operating assets and liabilities:
Decrease (increase) in accounts receivable	24,178	-27,944
Decrease in accounts receivable—related party	13	2,047
Increase in prepaid expenses	-12,063	-771
(Decrease) increase in accounts payable and accrued liabilities	-290	43,406
Settlement of asset retirement obligation	-981	-1,695
Net cash provided by operating activities	99,037	156,150
Cash flows from investing activities:
Deductions to cash held in escrow	8	8
Additions to other property and equipment	-632	-1,002
Additions to oil and gas properties	-226,905	-420,431
Proceeds from sale of oil and gas properties	1,314	0
Contributions to equity method investments	-6,093	-23,687
Distributions from equity method investments	817	0
Net cash used in investing activities	-231,491	-445,112
Cash flows from financing activities:
Principal payments on borrowings	-50,045	-42
Borrowings on line of credit	115,000	0
Debt issuance costs and loan commitment fees	-101	-185
Proceeds from issuance of common stock, net of offering costs and exercise of stock options		615
Net cash provided by financing activities	64,854	388
Net decrease in cash and cash equivalents	-67,600	-288,574
Cash and cash equivalents at beginning of period	142,340	458,956
Cash and cash equivalents at end of period	74,740	170,382
Supplemental disclosure of cash flow information:
Interest payments	240	18
Income tax payments	29,750	13,000
Supplemental disclosure of non-cash transactions:
Capitalized stock based compensation	1,385	1,723
Asset retirement obligation capitalized	1,584	1,869
Interest capitalized	3,694	2,318
Foreign currency translation loss on investment in Grizzly Oil Sands ULC	($14,984)	($7,278)

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS
	In February 2014, the Company entered into a definitive agreement with Rhino Exploration LLC ("Rhino") to acquire additional oil and natural gas properties consisting of approximately 8,000 net acres in the Utica Shale, as well as Rhino's interest in all of the producing wells on this acreage (the "Rhino Acquisition"). The Company purchased approximately $182.0 million ($179.5 million net of purchase price adjustments) of these assets in 2014.
	The Rhino Acquisition qualified as a business combination for accounting purposes and, as such, the Company estimated the fair value of the acquired properties as of the March 20, 2014 acquisition date. The fair value of the assets and liabilities acquired was estimated using assumptions that represent Level 3 inputs. See Note 10 - "Fair Value Measurements" for additional discussion of the measurement inputs.
	The Company estimated that the consideration paid in the Rhino Acquisition for these properties approximated the fair value that would be paid by a typical market participant. As a result, no goodwill or bargain purchase gain was recognized in conjunction with the purchase.
	The following table summarizes the consideration paid in the Rhino Acquisition to acquire the properties and the fair value amount of the assets acquired as of March 20, 2014.
		(In thousands)
	Consideration paid
	Cash, net of purchase price adjustments	$	179,527
	Fair value of identifiable assets acquired
	Oil and natural gas properties
	Proved	$	31,961
	Unproved	6,263
	Unevaluated	141,303
	Fair value of net identifiable assets acquired	$	179,527

Property_And_Equipment

Property And Equipment	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Property And Equipment	PROPERTY AND EQUIPMENT
	The major categories of property and equipment and related accumulated depletion, depreciation, amortization and impairment as of March 31, 2015 and December 31, 2014 are as follows:
		March 31, 2015			December 31, 2014
		(In thousands)
	Oil and natural gas properties	$	4,177,962		$	3,923,154
	Office furniture and fixtures	11,133			10,752
	Building	5,724			5,398
	Land	2,194			2,194
	Total property and equipment	4,197,013			3,941,498
	Accumulated depletion, depreciation, amortization and impairment	(1,140,168		)	(1,050,879		)
	Property and equipment, net	$	3,056,845		$	2,890,619
	Included in oil and natural gas properties at March 31, 2015 is the cumulative capitalization of $79.9 million in general and administrative costs incurred and capitalized to the full cost pool. General and administrative costs capitalized to the full cost pool represent management’s estimate of costs incurred directly related to exploration and development activities such as geological and other administrative costs associated with overseeing the exploration and development activities. All general and administrative costs not directly associated with exploration and development activities were charged to expense as they were incurred. Capitalized general and administrative costs were approximately $7.2 million and $6.3 million for the three months ended March 31, 2015 and 2014, respectively.
	The following table summarizes the Company’s non-producing properties excluded from amortization by area at March 31, 2015:
		March 31, 2015
		(In thousands)
	Colorado	$	5,088
	Bakken	96
	Southern Louisiana	283
	Ohio	1,541,292
	Other	45
		$	1,546,804
	At December 31, 2014, approximately $1.5 billion of non-producing leasehold costs was not subject to amortization.
	The Company evaluates the costs excluded from its amortization calculation at least annually. Subject to industry conditions and the level of the Company’s activities, the inclusion of most of the above referenced costs into the Company’s amortization calculation is expected to occur within three to five years.
	A reconciliation of the Company's asset retirement obligation for the three months ended March 31, 2015 and 2014 is as follows:
		March 31, 2015			March 31, 2014
		(In thousands)
	Asset retirement obligation, beginning of period	$	17,938		$	15,083
	Liabilities incurred	1,584			1,869
	Liabilities settled	(981		)	(1,695		)
	Accretion expense	190			188
	Asset retirement obligation as of end of period	18,731			15,445
	Less current portion	75			795
	Asset retirement obligation, long-term	$	18,656		$	14,650
	On May 7, 2012, the Company entered into a contribution agreement with Diamondback Energy Inc. ("Diamondback"). Under the terms of the contribution agreement, the Company agreed to contribute to Diamondback, prior to the closing of the Diamondback initial public offering (“Diamondback IPO”), all its oil and natural gas interests in the Permian Basin (the "Contribution"). The Contribution was completed on October 11, 2012. At the closing of the Contribution, Diamondback issued to the Company (i) 7,914,036 shares of Diamondback common stock and (ii) a promissory note for $63.6 million, which was repaid to the Company at the closing of the Diamondback IPO on October 17, 2012. This aggregate consideration was subject to a post-closing cash adjustment based on changes in the working capital, long-term debt and certain other items of Diamondback O&G LLC, formerly Windsor Permian LLC ("Diamondback O&G"), as of the date of the Contribution. In January 2013, the Company received an additional payment from Diamondback of approximately $18.6 million as a result of this post-closing adjustment. Diamondback O&G is a wholly-owned subsidiary of Diamondback. Under the contribution agreement, the Company is generally responsible for all liabilities and obligations with respect to the contributed properties arising prior to the Contribution and Diamondback is responsible for such liabilities and obligations with respect to the contributed properties arising after the Contribution.
	Immediately upon completion of the Contribution, the Company owned a 35% equity interest in Diamondback, rather than leasehold interests in the Company’s Permian Basin acreage. Upon completion of the Diamondback IPO in October 2012, Gulfport owned approximately 21.4% of Diamondback's outstanding common stock. Following the Contribution, the Company has accounted for its interest in Diamondback as an equity investment. In November 2014, the Company sold all of the remaining shares of Diamondback common stock that it received in the Contribution and, as of March 31, 2015, Gulfport did not own any shares of Diamondback's common stock. See Note 3, "Equity Investments - Diamondback Energy, Inc."

Equity_Investments

Equity Investments	3 Months Ended
	Mar. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Equity Investments	EQUITY INVESTMENTS
	Investments accounted for by the equity method consist of the following as of March 31, 2015 and December 31, 2014:
				Carrying Value					(Income) loss from equity method investments
		Approximate Ownership %		March 31, 2015			December 31, 2014		Three months ended March 31,
									2015			2014
				(In thousands)
	Investment in Tatex Thailand II, LLC	23.5	%	$	—		$	—	$	—		$	—
	Investment in Tatex Thailand III, LLC	17.9	%	—			—		—			49
	Investment in Grizzly Oil Sands ULC	24.9999	%	167,186			180,218		4,142			2,001
	Investment in Bison Drilling and Field Services LLC	—	%	—			—		—			1,933
	Investment in Muskie Proppant LLC	—	%	—			—		—			534
	Investment in Timber Wolf Terminals LLC	50	%	1,007			1,013		6			—
	Investment in Windsor Midstream LLC	22.5	%	32,292			13,505		(18,787		)	(168		)
	Investment in Stingray Pressure Pumping LLC	—	%	—			—		—			513
	Investment in Stingray Cementing LLC	50	%	2,254			2,647		67			95
	Investment in Blackhawk Midstream LLC	48.5	%	—			—		(7,217		)	(84,787		)
	Investment in Stingray Logistics LLC	—	%	—			—		—			81
	Investment in Diamondback Energy, Inc.	—	%	—			—		—			(48,767		)
	Investment in Stingray Energy Services LLC	50	%	6,167			5,718		10			41
	Investment in Sturgeon Acquisitions LLC	25	%	22,258			22,507		(568		)	—
	Investment in Mammoth Energy Partners LP	30.5	%	143,807			143,973		2,372			—
				$	374,971		$	369,581	$	(19,975	)	$	(128,475	)
	The tables below summarize financial information for the Company's equity investments as of March 31, 2015 and December 31, 2014.
	Summarized balance sheet information:
		March 31, 2015			December 31, 2014
		(In thousands)
	Current assets	$	151,752		$	181,060
	Noncurrent assets	$	1,419,656		$	1,306,891
	Current liabilities	$	55,369		$	114,506
	Noncurrent liabilities	$	213,050		$	230,062
	Summarized results of operations:
		Three months ended March 31,
		2015			2014
		(In thousands)
	Gross revenue	$	133,556		$	158,281
	Net income	$	90,668		$	181,505
	Tatex Thailand II, LLC
	The Company has an indirect ownership interest in Tatex Thailand II, LLC (“Tatex”). Tatex holds 85,122 of the 1,000,000 outstanding shares of APICO, LLC (“APICO”), an international oil and gas exploration company. APICO has a reserve base located in Southeast Asia through its ownership of concessions covering approximately 243,000 acres which includes the Phu Horm Field.
	Tatex Thailand III, LLC
	The Company has an ownership interest in Tatex Thailand III, LLC ("Tatex III"). Tatex III previously owned a concession covering approximately 245,000 acres in Southeast Asia. As of December 31, 2014, the Company reviewed its investment in Tatex III and made the decision to allow the concession to expire in 2015. As such, the Company fully impaired the asset as of December 31, 2014. The concession expired in January 2015.
	Grizzly Oil Sands ULC
	The Company, through its wholly owned subsidiary Grizzly Holdings Inc. ("Grizzly Holdings"), owns an interest in Grizzly Oil Sands ULC ("Grizzly"), a Canadian unlimited liability company. The remaining interest in Grizzly is owned by Grizzly Oil Sands Inc. ("Oil Sands"). As of March 31, 2015, Grizzly had approximately 830,000 acres under lease in the Athabasca and Peace River oil sands regions of Alberta, Canada. Initiation of steam injection at its first project, Algar Lake Phase 1, commenced in January 2014 and first bitumen production was achieved during the second quarter of 2014. In April 2015, Grizzly determined to cease bitumen production at its Algar Lake facility due to the current level of commodity prices. Grizzly intends to monitor market conditions as it assesses future plans for the facility. The Company reviewed its investment in Grizzly at March 31, 2015 and determined no impairment was needed. During the three months ended March 31, 2015, Gulfport paid $6.1 million in cash calls. Grizzly’s functional currency is the Canadian dollar. The Company's investment in Grizzly was decreased by $15.0 million and $7.3 million as a result of a foreign currency translation loss for the three months ended March 31, 2015 and 2014, respectively.
	Bison Drilling and Field Services LLC
	During 2011, the Company invested in Bison Drilling and Field Services LLC (“Bison”). Bison owns and operates drilling rigs. The Company contributed its investment in Bison to Mammoth Energy Partners LP ("Mammoth") during the fourth quarter of 2014. See below under "-Mammoth Energy Partners LP" for a discussion of the contribution.
	Muskie Proppant LLC
	During 2011, the Company invested in Muskie Proppant LLC (“Muskie”). Muskie processes and sells sand for use in hydraulic fracturing by the oil and natural gas industry and holds certain rights in a lease covering land in Wisconsin for mining oil and natural gas fracture grade sand. The income from equity method investments presented in the table above reflects any intercompany profit eliminations. The Company contributed its investment in Muskie to Mammoth during the fourth quarter of 2014. See below under "-Mammoth Energy Partners LP" for a discussion of the contribution.
	Timber Wolf Terminals LLC
	During 2012, the Company invested in Timber Wolf Terminals LLC (“Timber Wolf”). Timber Wolf will operate a crude/condensate terminal and a sand transloading facility in Ohio. During the three months ended March 31, 2015, Gulfport did not pay any cash calls related to Timber Wolf.
	Windsor Midstream LLC
	During 2012, the Company purchased an ownership interest in Windsor Midstream LLC (“Midstream”). Midstream owned a 28.4% interest in Coronado Midstream LLC ("Coronado"), a gas processing plant in West Texas. During the three months ended March 31, 2015, Gulfport did not pay any cash calls to Midstream.
	In March 2015, Coronado was sold to Enlink Midstream Partners, LP ("EnLink") for proceeds of approximately $600 million, consisting of cash and units representing a limited partnership interest in Enlink. Based on preliminary information available at the time of the sale, Midstream recorded an approximately $85.5 million gain on the sale of its investment in Coronado, which amount is subject to change.
	Stingray Pressure Pumping LLC
	During 2012, the Company invested in Stingray Pressure Pumping LLC ("Stingray Pressure"). Stingray Pressure provides well completion services. The income from equity method investments presented in the table above reflects any intercompany profit eliminations. The Company contributed its investment in Stingray Pressure to Mammoth during the fourth quarter of 2014. See below under "-Mammoth Energy Partners LP" for a discussion of the contribution.
	Stingray Cementing LLC
	During 2012, the Company invested in Stingray Cementing LLC ("Stingray Cementing"). Stingray Cementing provides well cementing services. During the three months ended March 31, 2015, the Company did not pay any cash calls related to Stingray Cementing. The income from equity method investments presented in the table above reflects any intercompany profit eliminations.
	Blackhawk Midstream LLC
	During 2012, the Company invested in Blackhawk Midstream LLC ("Blackhawk"). Blackhawk coordinates gathering, compression, processing and marketing activities for the Company in connection with the development of its Utica Shale acreage. On January 28, 2014, Blackhawk closed on the sale of its equity interests in Ohio Gathering Company, LLC and Ohio Condensate Company, LLC for a purchase price of $190.0 million, of which $14.3 million was placed in escrow. Gulfport received $84.8 million in net proceeds from this transaction in the first quarter of 2014, which is included in income from equity method investments in the consolidated statements of operations. During the first quarter of 2015, the Company received net proceeds of approximately $7.2 million from the release of escrow from the Blackhawk sale, which is included in income from equity method investments in the consolidated statements of operations.
	Stingray Logistics LLC
	During 2012, the Company invested in Stingray Logistics LLC ("Stingray Logistics"). Stingray Logistics provides well services. The Company contributed its investment in Stingray Logistics to Mammoth during the fourth quarter of 2014. See below under "-Mammoth Energy Partners LP" for a discussion of the contribution.
	Diamondback Energy, Inc.
	As noted above in Note 2, on October 11, 2012, following the closing of the Diamondback IPO, the Company owned 7,914,036 shares of Diamondback's outstanding common stock for an initial investment in Diamondback valued at $138.5 million. In 2013, the Company sold an aggregate of 4,534,536 shares of its Diamondback common stock and received aggregate net proceeds of approximately $192.7 million. In June and September of 2014, the Company sold 1,000,000 and 1,437,500 shares of its Diamondback common stock, respectively, and received aggregate net proceeds of approximately $197.6 million. On November 12, 2014, the Company sold its remaining 942,000 shares of Diamondback common stock for net proceeds of approximately $60.8 million. As of March 31, 2015, the Company did not own any shares of Diamondback common stock.
	The Company accounted for its interest in Diamondback as an equity method investment and had elected the fair value option of accounting for this investment. While the Company's ownership interest in Diamondback was below 20% prior to the Company's sale of its remaining Diamondback common stock in November 2014, the Company had appointed a member of Diamondback's Board. The individual appointed by the Company continues to serve on Diamondback's Board and the Company had influence through this board seat. The Company recognized an aggregate gain of approximately $48.8 million on its investment in Diamondback for three months ended March 31, 2014, which is included in income from equity method investments in the consolidated statements of operations.
	Stingray Energy Services LLC
	During 2013, the Company invested in Stingray Energy Services LLC ("Stingray Energy"). Stingray Energy provides rental tools for land-based oil and natural gas drilling, completion and workover activities as well as the transfer of fresh water to wellsites. During the three months ended March 31, 2015, the Company did not pay any cash calls to Stingray Energy. The income from equity method investments presented in the table above reflects any intercompany profit eliminations.
Sturgeon Acquisitions LLC
During 2014, the Company invested $20.7 million and received an ownership interest of 25% in Sturgeon Acquisitions LLC ("Sturgeon"). Sturgeon owns and operates sand mines that produce hydraulic fracturing grade sand. During the three months ended March 31, 2015, Gulfport received $0.8 million in distributions from Sturgeon.
Mammoth Energy Partners LP
In the fourth quarter of 2014, the Company contributed its investments in Stingray Pressure, Stingray Logistics, Bison and Muskie to Mammoth for a 30.5% interest in this newly formed limited partnership. Mammoth has filed a registration statement on Form S-1 with the SEC in connection with its proposed initial public offering. Mammoth intends to pursue this offering in 2015 subject to market conditions.
The Company accounted for the contribution as a sale of financial assets under ASC 860. The Company estimated the fair market value of its investment in Mammoth as of the contribution date using an average of the market approach and the income approach, based on an independently prepared valuation of the contributed assets. The fair market value was reduced by a discount factor for lack of marketability due to the Company's minority interest, resulting in a fair value of $143.5 million for the Company's 30.5% interest. The fair value of the assets and liabilities acquired was estimated using assumptions that represent Level 3 inputs. See "Note 10 - Fair Value Measurements" for additional discussion of the measurement inputs.

Other_Assets

Other Assets	3 Months Ended
	Mar. 31, 2015
Other Assets, Noncurrent Disclosure [Abstract]
Other Assets	OTHER ASSETS
	Prepaid expenses and other current assets consist of the following at March 31, 2015: prepaid taxes of $12.1 million, prepaid insurance of $2.3 million and prepaid other expense of $1.4 million.
	Other assets consist of the following as of March 31, 2015 and December 31, 2014:
		March 31, 2015		December 31, 2014
		(In thousands)
	Plugging and abandonment escrow account on the WCBB properties (Note 8)	$	3,089	$	3,097
	Certificates of Deposit securing letter of credit	275		275
	Prepaid drilling costs	269		483
	Loan commitment fees	14,771		15,390
	Deposits	34		34
	Other	128		117
		$	18,566	$	19,396

LongTerm_Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2015
Long-term Debt, Unclassified [Abstract]
Long-Term Debt	LONG-TERM DEBT
	Long-term debt consisted of the following items as of March 31, 2015 and December 31, 2014:
		March 31, 2015			December 31, 2014
		(In thousands)
	Revolving credit agreement (1)	$	165,000		$	100,000
	Building loans (2)	1,781			1,826
	7.75% senior unsecured notes due 2020 (3)	600,000			600,000
	Unamortized original issue (discount) premium, net (4)	14,130			14,658
	Less: current maturities of long term debt	(1,781		)	(168		)
	Debt reflected as long term (5)	$	779,130		$	716,316
	The Company capitalized approximately $3.7 million and $2.3 million in interest expense to oil and natural gas properties during the three months ended March 31, 2015 and 2014, respectively.
	(1) On December 27, 2013, the Company entered into an Amended and Restated Credit Agreement with The Bank of Nova Scotia, as administrative agent, sole lead arranger and sole bookrunner, Amegy Bank National Association, as syndication agent, KeyBank National Association, as documentation agent, and other lenders (The "Amended and Restated Credit Agreement") that provides for a maximum facility amount of $1.5 billion. The Amended and Restated Credit Agreement matures on June 6, 2018. The Company’s wholly-owned subsidiaries have guaranteed the obligations of the Company under the Amended and Restated Credit Agreement.
	On April 23, 2014, the Company entered into a first amendment to the Amended and Restated Credit Agreement. The first amendment increased the letter of credit sublimit from $20.0 million to $70.0 million and provided for an increase in the borrowing base availability from $150.0 million to $275.0 million. The first amendment also made certain changes to the lenders and their respective lending commitments thereunder.
	On November 26, 2014, the Company entered into a second amendment to the Amended and Restated Credit Agreement. The second amendment changed the definition of EBITDAX to exclude proceeds from the disposition of equity method investments and changed the ratio of funded debt to EBITDAX to be the ratio of net funded debt to EBITDAX. Net funded debt is funded debt less the amount of cash and short-term investments the Company has at the end of the relevant fiscal quarter. The second amendment increases the ratio from 2.00 to 1.00 to 3.50 to 1.00 for the period December 31, 2014 through June 30, 2015 and then decreases the ratio to 3.25 to 1.00 for the periods thereafter. Further, the second amendment increased the letter of credit sublimit from $70.0 million to $125.0 million and provided for an increase in the borrowing base availability from $275.0 million to $450.0 million. As of March 31, 2015, $165.0 million was outstanding under the Amended and Restated Credit Agreement. At March 31, 2015, the total availability for future borrowings under the Amended and Restated Credit Agreement, after giving effect to an aggregate of $68.2 million of letters of credit, was $216.8 million.
	On April 10, 2015, the Company entered into a third amendment to the Amended and Restated Credit Agreement. The third amendment increased the borrowing base from $450.0 million to $575.0 million and increased the Company's basket for unsecured debt issuances to $1.2 billion. The third amendment also made certain changes to the lenders and their respective lending commitments thereunder.
	Advances under the Amended and Restated Credit Agreement may be in the form of either base rate loans or eurodollar loans. The interest rate for base rate loans is equal to (1) the applicable rate, which ranges from 0.50% to 1.50%, plus (2) the highest of: (a) the federal funds rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by agent as its “prime rate,” and (c) the eurodollar rate for an interest period of one month plus 1.00%. The interest rate for eurodollar loans is equal to (1) the applicable rate, which ranges from 1.50% to 2.50%, plus (2) the London interbank offered rate that appears on pages LIBOR01 or LIBOR02 of the Reuters screen that displays such rate for deposits in U.S. dollars, or, if such rate is not available, the rate as administered by ICE Benchmark Administration (or any other person that takes over administration of such rate) per annum equal to the offered rate on such other page or service that displays on average London interbank offered rate as determined by ICE Benchmark Administration (or any other person that takes over administration of such rate) for deposits in U.S. dollars, or, if such rate is not available, the average quotations for three major New York money center banks of whom the agent shall inquire as the “London Interbank Offered Rate” for deposits in U.S. dollars. At March 31, 2015, amounts borrowed under the Amended and Restated Credit Agreement bore interest at the Eurodollar rate (2.18%).
	The Amended and Restated Credit Agreement contains customary negative covenants including, but not limited to, restrictions on the Company’s and its subsidiaries’ ability to:
	•incur indebtedness;
	•grant liens;
	•pay dividends and make other restricted payments;
	•make investments;
	•make fundamental changes;
	•enter into swap contracts and forward sales contracts;
	•dispose of assets;
	•change the nature of their business; and
	•enter into transactions with affiliates.
	The negative covenants are subject to certain exceptions as specified in the Amended and Restated Credit Agreement. The Amended and Restated Credit Agreement also contains certain affirmative covenants, including, but not limited to the following financial covenants:
	(i) the ratio of net funded debt to EBITDAX (net income, excluding (i) any non-cash revenue or expense associated with swap contracts resulting from ASC 815 and (ii) any cash or noncash revenue or expense attributable to minority investments plus without duplication and, in the case of expenses, to the extent deducted from revenues in determining net income, the sum of (a) the aggregate amount of consolidated interest expense for such period, (b) the aggregate amount of income, franchise, capital or similar tax expense (other than ad valorem taxes) for such period, (c) all amounts attributable to depletion, depreciation, amortization and asset or goodwill impairment or writedown for such period, (d) all other non-cash charges, (e) exploration costs deducted in determining net income under successful efforts accounting, (f) actual cash distributions received from minority investments, (g) to the extent actually reimbursed by insurance, expenses with respect to liability on casualty events or business interruption, and (h) all reasonable transaction expenses related to dispositions and acquisitions of assets, investments and debt and equity offerings (provided that expenses related to any unsuccessful disposition will be limited to $3.0 million in the aggregate) for a twelve-month period may not be greater than 3.50 to 1.00; for the period December 31, 2014 through June 30, 2015 and 3.25 to 1.00 for the twelve-month period ending September 30, 2015 and periods thereafter; and
	(ii) the ratio of EBITDAX to interest expense for a twelve-month period may not be less than 3.00 to 1.00.
	The Company was in compliance with all covenants at March 31, 2015.
	(2) In March 2011, the Company entered into a new building loan agreement for the office building it occupies in Oklahoma City, Oklahoma. The new loan agreement refinanced the $2.4 million outstanding under the previous building loan agreement. The new agreement matures in February 2016 and bears interest at the rate of 5.82% per annum. The new building loan requires monthly interest and principal payments of approximately $22,000 and is collateralized by the Oklahoma City office building and associated land.
	(3) On October 17, 2012, the Company issued $250.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "October Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act (the "October Notes Offering") under an indenture among the Company, its subsidiary guarantors and Wells Fargo Bank, National Association, as the trustee (the "senior note indenture"). On December 21, 2012, the Company issued an additional $50.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "December Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the December Notes Offering"). The December Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the October Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of the October Notes Offering and the net proceeds of the December Notes Offering for general corporate purposes, which included funding a portion of its 2013 capital development plan. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act in October 2013 (the "Exchange Notes").
	On August 18, 2014, the Company issued an additional $300.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "August Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the August Notes Offering"). The August Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the August Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company intends to use the remaining net proceeds of the August Notes Offering for general corporate purposes, including funding a portion of its 2014 and 2015 capital development plans. The October Notes Offering, December Notes Offering and the August Notes Offering are collectively referred to as the "Notes Offerings" and the Exchange Notes, and the August Notes are collectively referred to as the "Old Notes".
	In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Notes was completed in March 2015.
	Under the senior note indenture relating to the Old Notes, interest on the Old Notes accrues at a rate of 7.75% per annum on the outstanding principal amount from October 17, 2012, payable semi-annually on May 1 and November 1 of each year, commencing on May 1, 2013. The Old Notes are the Company's senior unsecured obligations and rank equally in the right of payment with all of the Company's other senior indebtedness and senior in right of payment to any future subordinated indebtedness. All of the Company's existing and future restricted subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt guarantee the Old Notes; provided, however, that the Old Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company's future unrestricted subsidiaries. The Company may redeem some or all of the Old Notes at any time on or after November 1, 2016, at the redemption prices listed in the senior note indenture. Prior to November 1, 2016, the Company may redeem the Old Notes at a price equal to 100% of the principal amount plus a “make-whole” premium. In addition, prior to November 1, 2015, the Company may redeem up to 35% of the aggregate principal amount of the Old Notes with the net proceeds of certain equity offerings, provided that at least 65% of the aggregate principal amount of the Old Notes initially issued remains outstanding immediately after such redemption.
	(4) The October Notes were issued at a price of 98.534% resulting in a gross discount of $3.7 million and an effective rate of 8.000%. The December Notes were issued at a price of 101.000% resulting in a gross premium of $0.5 million and an effective rate of 7.531%. The August Notes were issued at a price of 106.000% resulting in a gross premium of $18.0 million and an effective rate of 6.561%. The premium and discount are being amortized using the effective interest method.
	(5) Does not reflect the Company's issuance of $350.0 million in aggregate principal amount of 6.625% Senior Notes due 2023 on April 21, 2015. See Note 14 - "Subsequent Events" below.

StockBased_Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2015
Share-based Compensation [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION
	During the three months ended March 31, 2015 and 2014, the Company’s stock-based compensation cost was $3.5 million and $4.3 million, respectively, of which the Company capitalized $1.4 million and $1.7 million, respectively, relating to its exploration and development efforts.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes option valuation model. Expected volatilities are based on the historical volatility of the market price of Gulfport’s common stock over a period of time ending on the grant date. Based upon the historical experience of the Company, the expected term of options granted is equal to the vesting period plus one year. The risk-free rate for periods within the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of the grant. The 2013 Restated Stock Incentive Plan (which amended and restated the 2005 Plan) provides that all options must have an exercise price not less than the fair value of the Company’s common stock on the date of the grant.
	No stock options were issued during the three months ended March 31, 2015 and 2014.
	The Company has not declared dividends and does not intend to do so in the foreseeable future, and thus did not use a dividend yield. In each case, the actual value that will be realized, if any, depends on the future performance of the common stock and overall stock market conditions. There is no assurance that the value an optionee actually realizes will be at or near the value estimated using the Black-Scholes model.
	A summary of the status of stock options and related activity for the three months ended March 31, 2015 is presented below:
		Shares		Weighted			Weighted		Aggregate
				Average			Average		Intrinsic
				Exercise Price			Remaining		Value (In thousands)
				per Share			Contractual Term
	Options outstanding at December 31, 2014	5,000		$	9.07		0.69		$	163
	Granted	—		—
	Exercised	—		—					—
	Forfeited/expired	—		—
	Options outstanding at March 31, 2015	5,000		$	9.07		0.44		$	184
	Options exercisable at March 31, 2015	5,000		$	9.07		0.44		$	184
	The following table summarizes information about the stock options outstanding at March 31, 2015:
	Exercise			Number		Weighted Average		Number
	Price			Outstanding		Remaining Life		Exercisable
						(in years)
	$	9.07		5,000		0.44		5,000
				5,000				5,000
	The following table summarizes restricted stock activity for the three months ended March 31, 2015:
		Number of		Weighted
		Unvested		Average
		Restricted Shares		Grant Date
				Fair Value
	Unvested shares as of December 31, 2014	387,245		$	55.87
	Granted	100,226		44.04
	Vested	(60,381	)	52.94
	Forfeited	—		—
	Unvested shares as of March 31, 2015	427,090		$	53.51
	Unrecognized compensation expense as of March 31, 2015 related to outstanding stock options and restricted shares was $18.9 million. The expense is expected to be recognized over a weighted average period of 1.55 years.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE
	Reconciliations of the components of basic and diluted net income per common share are presented in the tables below:
		Three months ended March 31,
		2015					2014
		Income		Shares	Per		Income		Shares	Per
					Share					Share
		(In thousands, except share data)
	Basic:
	Net income	$	25,519	85,679,606	$	0.3	$	82,558	85,259,407	$	0.97
	Effect of dilutive securities:
	Stock options and awards	—		440,424			—		479,219
	Diluted:
	Net income	$	25,519	86,120,030	$	0.3	$	82,558	85,738,626	$	0.96
	There were no potential shares of common stock that were considered anti-dilutive for the three months ended March 31, 2015 and 2014.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES
	Plugging and Abandonment Funds
	In connection with the Company's acquisition in 1997 of the remaining 50% interest in its WCBB properties, the Company assumed the seller’s (Chevron) obligation to contribute approximately $18,000 per month through March 2004 to a plugging and abandonment trust and the obligation to plug a minimum of 20 wells per year for 20 years commencing March 11, 1997. Chevron retained a security interest in production from these properties until the Company's abandonment obligations to Chevron have been fulfilled. Beginning in 2009, the Company could access the trust for use in plugging and abandonment charges associated with the property, although it has not yet done so. As of March 31, 2015, the plugging and abandonment trust totaled approximately $3.1 million. At March 31, 2015, the Company had plugged 463 wells at WCBB since it began its plugging program in 1997, which management believes fulfills its current minimum plugging obligation.
	Employment Agreements
	Effective November 1, 2012, the Company entered into an employment agreement with Messrs. James Palm, Mike Liddell and Michael G. Moore, each with an initial three-year term expiring on November 1, 2015 subject to automatic one-year extensions unless terminated by either party to the agreement at least 90 days prior to the end of the then current term. These agreements provided for minimum salary and bonus levels, subject to review and potential increase by the Compensation Committee and/or the Board of Directors, as well as participation in the Company's incentive plans and other employee benefits.
	Effective February 15, 2014, Gulfport's former Chief Executive Officer, James D. Palm, retired and his employment agreement with the company terminated. The Company entered into a separation agreement with Mr. Palm, under which agreement certain benefits are provided to, and obligations imposed on, Mr. Palm. As of March 31, 2015, the minimum commitment under Mr. Palm's separation agreement was approximately $0.4 million.
	Mr. Liddell resigned as the Company's Chairman effective June 2013 at which date his employment agreement with Gulfport terminated. At that same time, the Company entered into a consulting agreement with Mr. Liddell. Mr. Liddell terminated his consulting agreement with the Company effective January 1, 2015.
	On April 22, 2014, the Board of Directors appointed Michael G. Moore as Chief Executive Officer of the Company. The Company and Mr. Moore entered into an amended and restated employment agreement. The agreement has a three-year term commencing effective April 22, 2014. This agreement provides, among other things, for a minimum salary level, subject to review and potential increase by the Compensation Committee and/or the Board of Directors, as well as participation in the Company's incentive plans and other employee benefits.
	On March 13, 2015, the Company entered into an employment agreement with Ross Kirtley, the Company's Chief Operating Officer. The agreement has a two-year term commencing effective April 22, 2014. This agreement provides, among other things, for a minimum salary level, subject to review and potential increase by the Compensation Committee and/or the Board of Directors, as well as participation in the Company's incentive plans and other employee benefits.
	On March 13, 2015, the Company entered into an employment agreement with Aaron Gaydosik, the Company's Chief Financial Officer. The agreement has a three-year term commencing effective August 11, 2014. This agreement provides, among other things, for a minimum salary level, subject to review and potential increase by the Compensation Committee and/or the Board of Directors, as well as participation in the Company's incentive plans and other employee benefits.
	The aggregate minimum commitment for future salary at March 31, 2015 under the above listed employment agreements was approximately $2.0 million.
	Effective as of April 29, 2015, the Company amended and restated its existing employment agreement with Mr. Moore. For a description of the amendments to Mr. Moore’s employment agreement, see Note 14 - “Subsequent Events.”
	Operating Leases
	The Company leases office facilities under non-cancellable operating leases exceeding one year. Future minimum lease commitments under these leases at March 31, 2015 were as follows:
		(In thousands)
	Remaining 2015	$	450
	2016	524
	2017	451
	2018	20
	2019	—
	Total	$	1,445
	Other Commitments
	Effective October 1, 2014, the Company entered into a Sand Supply Agreement with Muskie that expires on September 30, 2018. Pursuant to this agreement, the Company has agreed to purchase annual and monthly amounts of proppant sand subject to exceptions specified in the agreement at a fixed price per ton, subject to certain adjustments, plus agreed costs and expenses. Failure by either Muskie or the Company to deliver or accept the minimum monthly amount results in damages calculated per ton based on the difference between the monthly obligation amount and the amount actually delivered or accepted, as applicable. The Company did not incurred any expenses related to non-utilization fees during the three months ended March 31, 2015.
	Effective October 1, 2014, the Company entered into an Amended and Restated Master Services Agreement for pressure pumping services with Stingray Pressure that expires on September 30, 2018. Pursuant to this agreement, Stingray Pressure has agreed to provide hydraulic fracturing, stimulation and related completion and rework services to the Company and the Company has agreed to pay Stingray Pressure a monthly service fee plus the associated costs of the services provided.
	Future minimum commitments under these agreements at March 31, 2015 are as follows:
		(In thousands)
	Remaining 2015	$	39,330
	2016	52,440
	2017	52,440
	2018	39,330
	Total	$	183,540
	Litigation
	Due to the nature of the Company's business, it is, from time to time, involved in routine litigation or subject to disputes or claims related to its business activities, including workers' compensation claims and employment related disputes. In the opinion of the Company's management, none of the pending litigation, disputes or claims against the Company, if decided adversely, will have a material adverse effect on its financial condition, cash flows or results of operations.

Hedging_Activities

Hedging Activities	3 Months Ended
	Mar. 31, 2015
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Hedging Activities	HEDGING ACTIVITIES
	Oil Price Hedging Activities
	The Company seeks to reduce its exposure to unfavorable changes in oil and natural gas prices, which are subject to significant and often volatile fluctuation, by entering into fixed price swaps and basis swaps. These contracts allow the Company to predict with greater certainty the effective oil and natural gas prices to be received for hedged production and benefit operating cash flows and earnings when market prices are less than the fixed prices provided in the contracts. However, the Company will not benefit from market prices that are higher than the fixed prices in the contracts for hedged production.
	The Company accounts for its oil and natural gas derivative instruments as cash flow hedges for accounting purposes under FASB ASC 815 and related pronouncements. All derivative contracts are marked to market each quarter end and are included in the accompanying consolidated balance sheets as derivative assets and liabilities.
	During 2014 and 2015, the Company entered into fixed price swap contracts for 2014 through 2018 with four financial institutions. The Company’s fixed price swap contracts are tied to the commodity prices on Argus and NYMEX. The Company will receive the fixed price amount stated in the contract and pay to its counterparty the current market price as listed on Argus for Louisiana Light Sweet Crude for oil and on the NYMEX Henry Hub for natural gas. At March 31, 2015, the Company had the following fixed price swaps in place:
		Daily Volume		Weighted
		(Bbls/day)		Average Price
	April 2015 - June 2016	1,000		$	62.25
		Daily Volume (MMBtu/day)		Weighted
				Average Price
	Apr-15	191,250		$	4.05
	May 2015 - June 2015	201,250		$	4.05
	July 2015 - August 2015	216,875		$	4.04
	Sep-15	246,875		$	3.97
	October 2015 - December 2015	262,500		$	3.96
	January 2016 - March 2016	252,500		$	3.82
	Apr-16	242,500		$	3.81
	May 2016 - December 2016	172,500		$	3.73
	January 2017 - June 2017	142,500		$	3.67
	July 2017 - December 2017	80,000		$	3.45
	January 2018 - December 2018	30,000		$	3.4
	In addition, the Company has entered into natural gas basis swap positions, which settle on the pricing index to basis differential of MichCon to the NYMEX Henry Hub natural gas price. As of March 31, 2015, the Company's natural gas basis swap positions were as follows:
		Daily Volume (MMBtu/day)		Hedged Differential
	April 2015 - December 2016	30,000		$	0.02
	April 2015 - December 2016	10,000		$	0.01
	At March 31, 2015 the fair value of derivative assets and liabilities related to the fixed price swaps and basis swaps was as follows:
		(In thousands)
	Short-term derivative instruments - asset	$	93,030
	Long-term derivative instruments - asset	$	41,956
	Short-term derivative instruments - liability	$	823
	All fixed price swaps and basis swaps have been executed in connection with the Company’s oil and natural gas price hedging program. For fixed price swaps and basis swaps qualifying as cash flow hedges pursuant to FASB ASC 815, the realized contract price is included in oil and gas sales in the period for which the underlying production was hedged.
	For derivatives designated as cash flow hedges and meeting the effectiveness guidelines of FASB ASC 815, changes in fair value are recognized in accumulated other comprehensive income (loss) until the hedged item is recognized in earnings. The Company had no cash flow hedges in place for the three months ending March 31, 2015 and 2014, as all fixed price swaps and basis swaps were deemed ineffective at their inception.
	At March 31, 2015, no amounts related to fixed price swaps or basis swaps remain in accumulated other comprehensive loss.
	Hedge effectiveness is measured at least quarterly based on the relative changes in fair value between the derivative contract and the hedged item over time. Any change in fair value resulting from ineffectiveness is recognized immediately in earnings. The Company recognized a gain of $31.3 million related to hedge ineffectiveness for the three months ended March 31, 2015 which is included in oil and condensate and gas sales in the consolidated statements of operations. The Company recognized a loss of $8.7 million related to hedge ineffectiveness for the three months ended March 31, 2014 which is included in oil and condensate and gas sales in the consolidated statements of operations.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS
	The Company records certain financial and non-financial assets and liabilities on the balance sheet at fair value in accordance with FASB ASC 820. FASB ASC 820 defines fair value as the price that would be received to sell an asset or paid to transfer a liability (exit price) in an orderly transaction between market participants at the measurement date. The statement establishes market or observable inputs as the preferred sources of values, followed by assumptions based on hypothetical transactions in the absence of market inputs. The statement requires fair value measurements be classified and disclosed in one of the following categories:
	Level 1 – Quoted prices in active markets for identical assets and liabilities.
	Level 2 – Quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar instruments in markets that are not active and model-derived valuations whose inputs are observable or whose significant value drivers are observable.
	Level 3 – Significant inputs to the valuation model are unobservable.
	Financial assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurement.
	The following tables summarize the Company’s financial and non-financial liabilities by FASB ASC 820 valuation level as of March 31, 2015:
		March 31, 2015
		Level 1		Level 2		Level 3
		(In thousands)
	Assets:
	Fixed price swaps	$	134,986	$	—	$	—
	Liabilities:
	Fixed price swaps	$	823	$	—	$	—
	The estimated fair value of the Company’s fixed price and basis swap contracts were based upon forward commodity prices based on quoted market prices, adjusted for differentials. See Note 9 for further discussion of the Company's hedging activities.
	The estimated fair values of proved oil and gas properties assumed in business combinations are based on a discounted cash flow model and market assumptions as to future commodity prices, projections of estimated quantities of oil and natural gas reserves, expectations for timing and amount of future development and operating costs, projections of future rates of production, expected recovery rates, and risk-adjusted discount rates. The estimated fair values of unevaluated oil and gas properties was based on geological studies, historical well performance, location and applicable mineral lease terms. Based on the unobservable nature of certain of the inputs the estimated fair value of the oil and gas properties assumed is deemed to use Level 3 inputs. See Note 1 for further discussion of the Company's acquisitions.
	The Company estimates asset retirement obligations pursuant to the provisions of FASB ASC Topic 410, “Asset Retirement and Environmental Obligations” (“FASB ASC 410”). The initial measurement of asset retirement obligations at fair value is calculated using discounted cash flow techniques and based on internal estimates of future retirement costs associated with oil and gas properties. Given the unobservable nature of the inputs, including plugging costs and reserve lives, the initial measurement of the asset retirement obligation liability is deemed to use Level 3 inputs. See Note 2 for further discussion of the Company’s asset retirement obligations. Asset retirement obligations incurred during the three months ended March 31, 2015 were approximately $1.6 million.
	Due to the unobservable nature of the inputs, the fair value of the Company's initial investment in Mammoth was estimated using assumptions that represent level 3 inputs. The Company estimated the fair value of the investment as of the November 24, 2014 contribution date. See Note 3 for further discussion of the Company's contribution to Mammoth. The estimated fair value of the Company's investment in Mammoth was $143.5 million at December 31, 2014.

Fair_Value_Of_Financial_Instru

Fair Value Of Financial Instruments	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Fair Value Of Financial Instruments	FAIR VALUE OF FINANCIAL INSTRUMENTS
	The carrying amounts on the accompanying consolidated balance sheet for cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities, and current debt are carried at cost, which approximates market value due to their short-term nature. Long-term debt related to the building loan is carried at cost, which approximates market value based on the borrowing rates currently available to the Company with similar terms and maturities.
	At March 31, 2015, the carrying value of the outstanding debt represented by the Notes was $614.1 million, including the remaining unamortized discount of approximately $2.8 million related to the October Notes and the remaining unamortized premium of approximately $0.4 million related to the December Notes and $16.5 million related to the August Notes. Based on the quoted market price, the fair value of the Notes was determined to be approximately $615.8 million at March 31, 2015.
	The fair value of the derivative instruments is computed based on the difference between the prices provided by the fixed-price contracts and forward market prices as of the specified date, as adjusted for basis differentials, and for the Company's swaptions, market implied volatilities of the underlying commodity are also evaluated. Forward market prices for oil and natural gas are dependent upon supply and demand factors in such forward market and are subject to significant volatility.

Condensed_Consolidating_Financ

Condensed Consolidating Financial Information	3 Months Ended
	Mar. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Consolidating Financial Information	CONDENSED CONSOLIDATING FINANCIAL INFORMATION
	On October 17, 2012, December 21, 2012, and August 18, 2014, the Company issued an aggregate of $600.0 million principal amount of its 7.75% Senior Notes. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act. The Exchange Notes and the August Notes are collectively referred to as the "Notes". The Notes are guaranteed on a senior unsecured basis by all existing consolidated subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt (the "Guarantors"). The Notes are not guaranteed by Grizzly Holdings, Inc. (the "Non-Guarantor"). The Guarantors are 100% owned by Gulfport (the "Parent"), and the guarantees are full, unconditional, joint and several. There are no significant restrictions on the ability of the Parent or the Guarantors to obtain funds from each other in the form of a dividend or loan.
	In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Notes was completed in March 2015.
	The following condensed consolidating balance sheets, statements of operations, statements of comprehensive income (loss) and statements of cash flows are provided for the Parent, the Guarantors and the Non-Guarantor and include the consolidating adjustments and eliminations necessary to arrive at the information for the Company on a condensed consolidated basis. The information has been presented using the equity method of accounting for the Parent's ownership of the Guarantors and the Non-Guarantor.
	CONDENSED CONSOLIDATING BALANCE SHEETS
	(Amounts in thousands)
		March 31, 2015
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Assets
	Current assets:
	Cash and cash equivalents	$	73,667		$	1,072		$	1		$	—		$	74,740
	Accounts receivable - oil and gas	79,621			59			—			—			79,680
	Accounts receivable - related parties	33			—			—			—			33
	Accounts receivable - intercompany	48,154			26			—			(48,180		)	—
	Prepaid expenses and other current assets	15,777			—			—			—			15,777
	Short-term derivative instruments	93,030			—			—			—			93,030
	Total current assets	310,282			1,157			1			(48,180		)	263,260
	Property and equipment:
	Oil and natural gas properties, full-cost accounting	4,139,903			38,769			—			(710		)	4,177,962
	Other property and equipment	19,008			43			—			—			19,051
	Accumulated depletion, depreciation, amortization and impairment	(1,140,142		)	(26		)	—			—			(1,140,168		)
	Property and equipment, net	3,018,769			38,786			—			(710		)	3,056,845
	Other assets:
	Equity investments and investments in subsidiaries	365,840			—			167,186			(158,055		)	374,971
	Derivative instruments	41,956			—			—			—			41,956
	Other assets	18,566			—			—			—			18,566
	Total other assets	426,362			—			167,186			(158,055		)	435,493
	Total assets	$	3,755,413		$	39,943		$	167,187		$	(206,945	)	$	3,755,598
	Liabilities and Stockholders' Equity
	Current liabilities:
	Accounts payable and accrued liabilities	$	399,912		$	184		$	—		$	—		$	400,096
	Accounts payable - intercompany	—			48,072			108			(48,180		)	—
	Asset retirement obligation - current	75			—			—			—			75
	Short-term derivative instruments	823			—			—			—			823
	Deferred tax liability - current	29,622			—			—			—			29,622
	Current maturities of long-term debt	1,781			—			—			—			1,781
	Total current liabilities	432,213			48,256			108			(48,180		)	432,397
	Long-term derivative instrument	—			—			—			—			—
	Asset retirement obligation - long-term	18,656			—			—			—			18,656
	Deferred tax liability	215,122			—			—			—			215,122
	Long-term debt, net of current maturities	779,130			—			—			—			779,130
	Total liabilities	1,445,121			48,256			108			(48,180		)	1,445,305
	Stockholders' equity:
	Common stock	857			—			—			—			857
	Paid-in capital	1,832,062			321			233,174			(233,494		)	1,832,063
	Accumulated other comprehensive income (loss)	(41,659		)	—			(41,659		)	41,659			(41,659		)
	Retained earnings (accumulated deficit)	519,032			(8,634		)	(24,436		)	33,070			519,032
	Total stockholders' equity	2,310,292			(8,313		)	167,079			(158,765		)	2,310,293
	Total liabilities and stockholders' equity	$	3,755,413		$	39,943		$	167,187		$	(206,945	)	$	3,755,598
	CONDENSED CONSOLIDATING BALANCE SHEETS
	(Amounts in thousands)
		December 31, 2014
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Assets
	Current assets:
	Cash and cash equivalents	$	141,535		$	804		$	1		$	—		$	142,340
	Accounts receivable - oil and gas	103,762			96			—			—			103,858
	Accounts receivable - related parties	46			—			—			—			46
	Accounts receivable - intercompany	45,222			27			—			(45,249		)	—
	Prepaid expenses and other current assets	3,714			—			—			—			3,714
	Short-term derivative instruments	78,391			—			—			—			78,391
	Total current assets	372,670			927			1			(45,249		)	328,349
	Property and equipment:
	Oil and natural gas properties, full-cost accounting,	3,887,874			35,990			—			(710		)	3,923,154
Other property and equipment	18,301			43			—			—			18,344
Accumulated depletion, depreciation, amortization and impairment	(1,050,855		)	(24		)	—			—			(1,050,879		)
Property and equipment, net	2,855,320			36,009			—			(710		)	2,890,619
Other assets:
Equity investments and investments in subsidiaries	360,238			—			180,217			(170,874		)	369,581
Derivative instruments	24,448			—			—			—			24,448
Other assets	19,396			—			—			—			19,396
Total other assets	404,082			—			180,217			(170,874		)	413,425
Total assets	$	3,632,072		$	36,936		$	180,218		$	(216,833	)	$	3,632,393
Liabilities and Stockholders' Equity
Current liabilities:
Accounts payable and accrued liabilities	$	371,089		$	321		$	—		$	—		$	371,410
Accounts payable - intercompany	—			45,143			106			(45,249		)	—
Asset retirement obligation - current	75			—			—			—			75
Deferred tax liability	27,070			—			—			—			27,070
Current maturities of long-term debt	168			—			—			—			168
Total current liabilities	398,402			45,464			106			(45,249		)	398,723
Asset retirement obligation - long-term	17,863			—			—			—			17,863
Deferred tax liability	203,195			—			—			—			203,195
Long-term debt, net of current maturities	716,316			—			—			—			716,316
Total liabilities	1,335,776			45,464			106			(45,249		)	1,336,097
Stockholders' equity:
Common stock	856			—			—			—			856
Paid-in capital	1,828,602			322			227,079			(227,401		)	1,828,602
Accumulated other comprehensive income (loss)	(26,675		)	—			(26,675		)	26,675			(26,675		)
Retained earnings (accumulated deficit)	493,513			(8,850		)	(20,292		)	29,142			493,513
Total stockholders' equity	2,296,296			(8,528		)	180,112			(171,584		)	2,296,296
Total liabilities and stockholders' equity	$	3,632,072		$	36,936		$	180,218		$	(216,833	)	$	3,632,393
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
(Amounts in thousands)
	Three months ended March 31, 2015
	Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
Total revenues	$	175,832		$	485		$	—		$	—		$	176,317
Costs and expenses:
Lease operating expenses	16,787			193			—			—			16,980
Production taxes	4,253			32			—			—			4,285
Midstream gathering and processing	25,374			7			—			—			25,381
Depreciation, depletion, and amortization	89,908			1			—			—			89,909
General and administrative	10,761			36			2			—			10,799
Accretion expense	190			—			—			—			190
	147,273			269			2			—			147,544
INCOME FROM OPERATIONS	28,559			216			(2		)	—			28,773
OTHER (INCOME) EXPENSE:
Interest expense	8,759			—			—			—			8,759
Interest income	(9		)	—			—			—			(9		)
(Income) loss from equity method investments and investments in subsidiaries	(20,189		)	—			4,142			(3,928		)	(19,975		)
	(11,439		)	—			4,142			(3,928		)	(11,225		)
INCOME (LOSS) BEFORE INCOME TAXES	39,998			216			(4,144		)	3,928			39,998
INCOME TAX EXPENSE	14,479			—			—			—			14,479
NET INCOME (LOSS)	$	25,519		$	216		$	(4,144	)	$	3,928		$	25,519
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
(Amounts in thousands)
	Three months ended March 31, 2014
	Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
Total revenues	$	117,850		$	179		$	—		$	—		$	118,029
Costs and expenses:
Lease operating expenses	11,381			248			—			—			11,629
Production taxes	6,937			20			—			—			6,957
Midstream gathering and processing	7,757			12			—			—			7,769
Depreciation, depletion, and amortization	56,877			—			—			—			56,877
General and administrative	9,488			27			(4		)	—			9,511
Accretion expense	188			—			—			—			188
Gain on sale of assets	(11		)	—			—			—			(11		)
	92,617			307			(4		)	—			92,920
INCOME (LOSS) FROM OPERATIONS	25,233			(128		)	4			—			25,109
OTHER (INCOME) EXPENSE:
Interest expense	3,885			—			—			—			3,885
Interest income	(106		)	—			—			—			(106		)
Litigation settlement	18,000			—			—			—			18,000
(Income) loss from equity method investments and investments in subsidiaries	(128,351		)	—			2,001			(2,125		)	(128,475		)
	(106,572		)	—			2,001			(2,125		)	(106,696		)
INCOME (LOSS) BEFORE INCOME TAXES	131,805			(128		)	(1,997		)	2,125			131,805
INCOME TAX EXPENSE	49,247			—			—			—			49,247
NET INCOME (LOSS)	$	82,558		$	(128	)	$	(1,997	)	$	2,125		$	82,558
CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS)
(Amounts in thousands)
	Three months ended March 31, 2015
	Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
Net income (loss)	$	25,519		$	216		$	(4,144	)	$	3,928		$	25,519
Foreign currency translation adjustment	(14,984		)	—			(14,984		)	14,984			(14,984		)
Other comprehensive income (loss)	(14,984		)	—			(14,984		)	14,984			(14,984		)
Comprehensive income (loss)	$	10,535		$	216		$	(19,128	)	$	18,912		$	10,535
	Three months ended March 31, 2014
	Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
Net income (loss)	$	82,558		$	(128	)	$	(1,997	)	$	2,125		$	82,558
Foreign currency translation adjustment	(7,278		)	—			(7,278		)	7,278			(7,278		)
Other comprehensive income (loss)	(7,278		)	—			(7,278		)	7,278			(7,278		)
Comprehensive income (loss)	$	75,280		$	(128	)	$	(9,275	)	$	9,403		$	75,280
CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS
(Amounts in thousands)
	Three months ended March 31, 2015
	Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
Net cash provided by operating activities	$	95,879		$	3,158		$	—		$	—		$	99,037
Net cash provided by (used in) investing activities	(228,601		)	(2,890		)	(6,093		)	6,093			(231,491		)
Net cash provided by (used in) financing activities	64,854			—			6,093			(6,093		)	64,854
Net (decrease) increase in cash and cash equivalents	(67,868		)	268			—			—			(67,600		)
Cash and cash equivalents at beginning of period	141,535			804			1			—			142,340
Cash and cash equivalents at end of period	$	73,667		$	1,072		$	1		$	—		$	74,740
	Three months ended March 31, 2014
	Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
Net cash provided by (used in) operating activities	$	159,736		$	(3,585	)	$	(1	)	$	—		$	156,150
Net cash provided by (used in) investing activities	(443,079		)	(2,034		)	(8,069		)	8,070			(445,112		)
Net cash provided by (used in) financing activities	388			—			8,070			(8,070		)	388
Net decrease in cash and cash equivalents	(282,955		)	(5,619		)	—			—			(288,574		)
Cash and cash equivalents at beginning of period	451,431			7,525			—			—			458,956
Cash and cash equivalents at end of period	$	168,476		$	1,906		$	—		$	—		$	170,382

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Recent Accounting Pronouncements	RECENT ACCOUNTING PRONOUNCEMENTS
	In April 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-08: Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360) - Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. ASU 2014-08 changes the threshold for a disposal to qualify as a discontinued operation and requires new disclosures of both discontinued operations and certain other material disposal transactions that do not meet the revised definition of a discontinued operation. Under the updated standard, a disposal of a component or group of components of an entity is required to be reported as discontinued operations if the disposal represents a strategic shift that has (or will have) a major effect on an entity’s operations and financial results when the component or group of components of the entity (1) has been disposed of by a sale, (2) has been disposed of other than by sale or (3) is classified as held for sale. The ASU is effective for annual and interim periods beginning after December 15, 2014, however, early adoption is permitted. The Company early adopted this ASU on a prospective basis beginning with the second quarter of 2014. The adoption did not have a material impact on the Company’s consolidated financial statements.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which supersedes the revenue recognition requirements in Topic 605, Revenue Recognition, and most industry-specific guidance. The core principle of the new standard is for the recognition of revenue to depict the transfer of goods or services to customers in amounts that reflect the payment to which the company expects to be entitled in exchange for those goods or services. The new standard will also result in enhanced revenue disclosures, provide guidance for transactions that were not previously addressed comprehensively and improve guidance for multiple-element arrangements. The ASU is effective for annual periods beginning after December 15, 2016, and interim periods within those years, using either a full or a modified retrospective application approach. The Company is in the process of evaluating the impact on its consolidated financial statements.
	In August 2014, the FASB issued ASU No. 2014-15, "Presentation of Financial Statements - Going Concern (Subtopic 205-40)." The new guidance addresses management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern and in certain circumstances to provide related footnote disclosures. The standard is effective for the annual period ending after December 15, 2016 and for annual and interim periods thereafter. Early adoption is permitted. The Company does not believe that the adoption of this guidance will have a material impact on its consolidated financial statements.
	In April 2015, the FASB issued ASU No. 2015-03, "Simplifying the Presentation of Debt Issuance Costs (ASU 2015-03)." To simplify presentation of debt issuance costs, ASU 2015-03 requires that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts. ASU 2015-03 is effective for public entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The Company is in the process of assessing the effects of adoption of this new guidance.

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS
	Pending Acquisition
	On April 15, 2015, the Company entered into an agreement to acquire Paloma Partners III, LLC ("Paloma") for a total purchase price of approximately $301.3 million, subject to closing adjustments. Paloma holds approximately 24,000 net nonproducing acres in the Utica Shale of Ohio. This transaction is expected to close during the third quarter of 2015, subject to the satisfaction of certain closing conditions.
	Equity Offering
	On April 21, 2015, the Company issued 10,925,000 shares of its common stock in an underwritten public offering (which included the 1,425,000 shares sold pursuant to the option to purchase additional shares of the Company's common stock granted by the Company to, and exercised in full by, the underwriters). The net proceeds from the equity offering (including the net proceeds from the sale of the shares of common stock to the underwriters pursuant to their option to purchase additional shares) was approximately $501.9 million after underwriter discounts and commissions and estimated offering expenses. The Company used a portion of these net proceeds, together with a portion of the net proceeds from its concurrent senior notes offering, to repay all amounts outstanding at that time under its revolving credit facility and intends to use the remaining net proceeds from these offerings to fund the pending acquisition of Paloma and for general corporate purposes, including the funding of a portion of its 2015 capital development plans.
	Senior Notes due 2023
	On April 21, 2015, the Company issued $350.0 million in aggregate principal amount of 6.625% Senior Notes due 2023 (the “April Notes”) to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act (the “April Notes Offering”). The Company received net proceeds of approximately $343.6 million after initial purchaser discounts and commissions and estimated offering expenses.
	The April Notes were issued under an indenture, dated as of April 21, 2015, among the Company, the subsidiary guarantors party thereto and Wells Fargo Bank, N.A., as trustee. Pursuant to the indenture relating to the April Notes, interest on the April Notes will accrue at a rate of 6.625% per annum on the outstanding principal amount thereof from April 21, 2015, payable semi-annually on May 1 and November 1 of each year, commencing on November 1, 2015. The April Notes will mature on May 1, 2023.
	The April Notes are the Company’s senior unsecured obligations and rank equally in right of payment with all of the Company’s other senior indebtedness, including the Old Notes, and senior in right of payment to any of the Company’s future subordinated indebtedness. All of the Company’s existing and future restricted subsidiaries that guarantee its secured revolving credit facility or certain other debt guarantee the April Notes, provided, however, that the April Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company’s future unrestricted subsidiaries.
	In connection with the April Notes Offering, the Company and its subsidiary guarantors entered into a registration rights agreement, dated as of April 21, 2015, pursuant to which the Company agreed to file a registration statement with respect to an offer to exchange the April Notes for a new issue of substantially identical debt securities registered under the Securities Act. The Company may be required to file a shelf registration statement to cover resales of the April Notes under certain circumstances. If the Company fails to satisfy certain obligations under the registration rights agreement, it agreed to pay additional interest to the holders of the April Notes as specified in the registration rights agreement.
	New Fixed Price Swaps
	In April 2015, the Company entered into fixed price swaps for 1,500 barrels of oil per day at a weighted average price of $62.47 per barrel for the period from June 2015 through June 2016. For the period from October 2015 through December 2015, the Company entered into fixed price swaps for 20,000 MMBtu of natural gas per day at a weighted average price of $3.26 per MMBtu. For the period from January 2016 through December 2016, the Company entered into fixed price swaps for 40,000 MMBtu of natural gas per day at a weighted average price of $3.32 per MMBtu. For the period from January 2017 through December 2018, the Company entered into fixed price swaps for 20,000 MMBtu of natural gas per day at a weighted average price of $3.26 per MMBtu. For the period from January 2016 through December 2016, the Company entered into a swaption contract for 20,000 MMBtu of natural gas per day at a weighted average price of $3.38 per MMBtu. The Company's fixed price swap contracts are tied to the commodity prices on NYMEX and ARGUS. The Company will receive the fixed price amount stated in the contract and pay to its counterparty the current market price as listed on NYMEX or ARGUS for oil.
	Amended and Restated Employment Agreement
	Effective as of April 29, 2015, the Company amended and restated its existing employment agreement with Michael G. Moore, the Company’s Chief Executive Officer. The employment agreement, as amended and restated as of April 29, 2015, reflects the decision of the compensation committee of the Company’s board of directors to increase Mr. Moore’s annual base salary to $460,000 for 2015 and the determination by the compensation committee to continue to increase Mr. Moore’s annual base salary during 2016 and 2017 so as to achieve alignment between the 25th and 50th percentile of the Company’s peer group disclosed in the Company’s annual proxy statement. The amended and restated employment agreement also eliminated Mr. Moore’s right to receive a fixed annual grant of 40,000 shares of restricted stock. Instead, consistent with the recommendation of the Company’s compensation consultant and approved by the compensation committee, the amended and restated employment agreement provided that Mr. Moore is entitled to receive an award of restricted stock equal to 500% of his annual base salary on the same vesting schedule as previously provided in his employment agreement with respect to his equity awards.

Recent_Accounting_Pronouncemen1

Recent Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Recent Accounting Pronouncements	In April 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-08: Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360) - Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. ASU 2014-08 changes the threshold for a disposal to qualify as a discontinued operation and requires new disclosures of both discontinued operations and certain other material disposal transactions that do not meet the revised definition of a discontinued operation. Under the updated standard, a disposal of a component or group of components of an entity is required to be reported as discontinued operations if the disposal represents a strategic shift that has (or will have) a major effect on an entity’s operations and financial results when the component or group of components of the entity (1) has been disposed of by a sale, (2) has been disposed of other than by sale or (3) is classified as held for sale. The ASU is effective for annual and interim periods beginning after December 15, 2014, however, early adoption is permitted. The Company early adopted this ASU on a prospective basis beginning with the second quarter of 2014. The adoption did not have a material impact on the Company’s consolidated financial statements.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which supersedes the revenue recognition requirements in Topic 605, Revenue Recognition, and most industry-specific guidance. The core principle of the new standard is for the recognition of revenue to depict the transfer of goods or services to customers in amounts that reflect the payment to which the company expects to be entitled in exchange for those goods or services. The new standard will also result in enhanced revenue disclosures, provide guidance for transactions that were not previously addressed comprehensively and improve guidance for multiple-element arrangements. The ASU is effective for annual periods beginning after December 15, 2016, and interim periods within those years, using either a full or a modified retrospective application approach. The Company is in the process of evaluating the impact on its consolidated financial statements.
	In August 2014, the FASB issued ASU No. 2014-15, "Presentation of Financial Statements - Going Concern (Subtopic 205-40)." The new guidance addresses management's responsibility to evaluate whether there is substantial doubt about an entity's ability to continue as a going concern and in certain circumstances to provide related footnote disclosures. The standard is effective for the annual period ending after December 15, 2016 and for annual and interim periods thereafter. Early adoption is permitted. The Company does not believe that the adoption of this guidance will have a material impact on its consolidated financial statements.
	In April 2015, the FASB issued ASU No. 2015-03, "Simplifying the Presentation of Debt Issuance Costs (ASU 2015-03)." To simplify presentation of debt issuance costs, ASU 2015-03 requires that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts. ASU 2015-03 is effective for public entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The Company is in the process of assessing the effects of adoption of this new guidance.

Acquisitions_Tables

Acquisitions (Tables)	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table summarizes the consideration paid in the Rhino Acquisition to acquire the properties and the fair value amount of the assets acquired as of March 20, 2014.
		(In thousands)
	Consideration paid
	Cash, net of purchase price adjustments	$	179,527
	Fair value of identifiable assets acquired
	Oil and natural gas properties
	Proved	$	31,961
	Unproved	6,263
	Unevaluated	141,303
	Fair value of net identifiable assets acquired	$	179,527

Property_And_Equipment_Tables

Property And Equipment (Tables)	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Schedule Of Property And Equipment	The major categories of property and equipment and related accumulated depletion, depreciation, amortization and impairment as of March 31, 2015 and December 31, 2014 are as follows:
		March 31, 2015			December 31, 2014
		(In thousands)
	Oil and natural gas properties	$	4,177,962		$	3,923,154
	Office furniture and fixtures	11,133			10,752
	Building	5,724			5,398
	Land	2,194			2,194
	Total property and equipment	4,197,013			3,941,498
	Accumulated depletion, depreciation, amortization and impairment	(1,140,168		)	(1,050,879		)
	Property and equipment, net	$	3,056,845		$	2,890,619
Summary Of Oil And Gas Properties Not Subject To Amortization	The following table summarizes the Company’s non-producing properties excluded from amortization by area at March 31, 2015:
		March 31, 2015
		(In thousands)
	Colorado	$	5,088
	Bakken	96
	Southern Louisiana	283
	Ohio	1,541,292
	Other	45
		$	1,546,804
Schedule Of Asset Retirement Obligation	A reconciliation of the Company's asset retirement obligation for the three months ended March 31, 2015 and 2014 is as follows:
		March 31, 2015			March 31, 2014
		(In thousands)
	Asset retirement obligation, beginning of period	$	17,938		$	15,083
	Liabilities incurred	1,584			1,869
	Liabilities settled	(981		)	(1,695		)
	Accretion expense	190			188
	Asset retirement obligation as of end of period	18,731			15,445
	Less current portion	75			795
	Asset retirement obligation, long-term	$	18,656		$	14,650

Equity_Investments_Tables

Equity Investments (Tables)	3 Months Ended
	Mar. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Investments Accounted For By The Equity Method	Investments accounted for by the equity method consist of the following as of March 31, 2015 and December 31, 2014:
				Carrying Value					(Income) loss from equity method investments
		Approximate Ownership %		March 31, 2015			December 31, 2014		Three months ended March 31,
									2015			2014
				(In thousands)
	Investment in Tatex Thailand II, LLC	23.5	%	$	—		$	—	$	—		$	—
	Investment in Tatex Thailand III, LLC	17.9	%	—			—		—			49
	Investment in Grizzly Oil Sands ULC	24.9999	%	167,186			180,218		4,142			2,001
	Investment in Bison Drilling and Field Services LLC	—	%	—			—		—			1,933
	Investment in Muskie Proppant LLC	—	%	—			—		—			534
	Investment in Timber Wolf Terminals LLC	50	%	1,007			1,013		6			—
	Investment in Windsor Midstream LLC	22.5	%	32,292			13,505		(18,787		)	(168		)
	Investment in Stingray Pressure Pumping LLC	—	%	—			—		—			513
	Investment in Stingray Cementing LLC	50	%	2,254			2,647		67			95
	Investment in Blackhawk Midstream LLC	48.5	%	—			—		(7,217		)	(84,787		)
	Investment in Stingray Logistics LLC	—	%	—			—		—			81
	Investment in Diamondback Energy, Inc.	—	%	—			—		—			(48,767		)
	Investment in Stingray Energy Services LLC	50	%	6,167			5,718		10			41
	Investment in Sturgeon Acquisitions LLC	25	%	22,258			22,507		(568		)	—
	Investment in Mammoth Energy Partners LP	30.5	%	143,807			143,973		2,372			—
				$	374,971		$	369,581	$	(19,975	)	$	(128,475	)
Equity Method Investment Balance Sheet Summary	Summarized balance sheet information:
		March 31, 2015			December 31, 2014
		(In thousands)
	Current assets	$	151,752		$	181,060
	Noncurrent assets	$	1,419,656		$	1,306,891
	Current liabilities	$	55,369		$	114,506
	Noncurrent liabilities	$	213,050		$	230,062
Equity Method Investment Income Statement Summary	Summarized results of operations:
		Three months ended March 31,
		2015			2014
		(In thousands)
	Gross revenue	$	133,556		$	158,281
	Net income	$	90,668		$	181,505

Other_Assets_Tables

Other Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Other Assets, Noncurrent Disclosure [Abstract]
Schedule Of Other Assets	Other assets consist of the following as of March 31, 2015 and December 31, 2014:
		March 31, 2015		December 31, 2014
		(In thousands)
	Plugging and abandonment escrow account on the WCBB properties (Note 8)	$	3,089	$	3,097
	Certificates of Deposit securing letter of credit	275		275
	Prepaid drilling costs	269		483
	Loan commitment fees	14,771		15,390
	Deposits	34		34
	Other	128		117
		$	18,566	$	19,396

LongTerm_Debt_Tables

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2015
Long-term Debt, Unclassified [Abstract]
Break-Down of Long-Term Debt	Long-term debt consisted of the following items as of March 31, 2015 and December 31, 2014:
		March 31, 2015			December 31, 2014
		(In thousands)
	Revolving credit agreement (1)	$	165,000		$	100,000
	Building loans (2)	1,781			1,826
	7.75% senior unsecured notes due 2020 (3)	600,000			600,000
	Unamortized original issue (discount) premium, net (4)	14,130			14,658
	Less: current maturities of long term debt	(1,781		)	(168		)
	Debt reflected as long term (5)	$	779,130		$	716,316
	The Company capitalized approximately $3.7 million and $2.3 million in interest expense to oil and natural gas properties during the three months ended March 31, 2015 and 2014, respectively.
	(1) On December 27, 2013, the Company entered into an Amended and Restated Credit Agreement with The Bank of Nova Scotia, as administrative agent, sole lead arranger and sole bookrunner, Amegy Bank National Association, as syndication agent, KeyBank National Association, as documentation agent, and other lenders (The "Amended and Restated Credit Agreement") that provides for a maximum facility amount of $1.5 billion. The Amended and Restated Credit Agreement matures on June 6, 2018. The Company’s wholly-owned subsidiaries have guaranteed the obligations of the Company under the Amended and Restated Credit Agreement.
	On April 23, 2014, the Company entered into a first amendment to the Amended and Restated Credit Agreement. The first amendment increased the letter of credit sublimit from $20.0 million to $70.0 million and provided for an increase in the borrowing base availability from $150.0 million to $275.0 million. The first amendment also made certain changes to the lenders and their respective lending commitments thereunder.
	On November 26, 2014, the Company entered into a second amendment to the Amended and Restated Credit Agreement. The second amendment changed the definition of EBITDAX to exclude proceeds from the disposition of equity method investments and changed the ratio of funded debt to EBITDAX to be the ratio of net funded debt to EBITDAX. Net funded debt is funded debt less the amount of cash and short-term investments the Company has at the end of the relevant fiscal quarter. The second amendment increases the ratio from 2.00 to 1.00 to 3.50 to 1.00 for the period December 31, 2014 through June 30, 2015 and then decreases the ratio to 3.25 to 1.00 for the periods thereafter. Further, the second amendment increased the letter of credit sublimit from $70.0 million to $125.0 million and provided for an increase in the borrowing base availability from $275.0 million to $450.0 million. As of March 31, 2015, $165.0 million was outstanding under the Amended and Restated Credit Agreement. At March 31, 2015, the total availability for future borrowings under the Amended and Restated Credit Agreement, after giving effect to an aggregate of $68.2 million of letters of credit, was $216.8 million.
	On April 10, 2015, the Company entered into a third amendment to the Amended and Restated Credit Agreement. The third amendment increased the borrowing base from $450.0 million to $575.0 million and increased the Company's basket for unsecured debt issuances to $1.2 billion. The third amendment also made certain changes to the lenders and their respective lending commitments thereunder.
	Advances under the Amended and Restated Credit Agreement may be in the form of either base rate loans or eurodollar loans. The interest rate for base rate loans is equal to (1) the applicable rate, which ranges from 0.50% to 1.50%, plus (2) the highest of: (a) the federal funds rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by agent as its “prime rate,” and (c) the eurodollar rate for an interest period of one month plus 1.00%. The interest rate for eurodollar loans is equal to (1) the applicable rate, which ranges from 1.50% to 2.50%, plus (2) the London interbank offered rate that appears on pages LIBOR01 or LIBOR02 of the Reuters screen that displays such rate for deposits in U.S. dollars, or, if such rate is not available, the rate as administered by ICE Benchmark Administration (or any other person that takes over administration of such rate) per annum equal to the offered rate on such other page or service that displays on average London interbank offered rate as determined by ICE Benchmark Administration (or any other person that takes over administration of such rate) for deposits in U.S. dollars, or, if such rate is not available, the average quotations for three major New York money center banks of whom the agent shall inquire as the “London Interbank Offered Rate” for deposits in U.S. dollars. At March 31, 2015, amounts borrowed under the Amended and Restated Credit Agreement bore interest at the Eurodollar rate (2.18%).
	The Amended and Restated Credit Agreement contains customary negative covenants including, but not limited to, restrictions on the Company’s and its subsidiaries’ ability to:
	•incur indebtedness;
	•grant liens;
	•pay dividends and make other restricted payments;
	•make investments;
	•make fundamental changes;
	•enter into swap contracts and forward sales contracts;
	•dispose of assets;
	•change the nature of their business; and
	•enter into transactions with affiliates.
	The negative covenants are subject to certain exceptions as specified in the Amended and Restated Credit Agreement. The Amended and Restated Credit Agreement also contains certain affirmative covenants, including, but not limited to the following financial covenants:
	(i) the ratio of net funded debt to EBITDAX (net income, excluding (i) any non-cash revenue or expense associated with swap contracts resulting from ASC 815 and (ii) any cash or noncash revenue or expense attributable to minority investments plus without duplication and, in the case of expenses, to the extent deducted from revenues in determining net income, the sum of (a) the aggregate amount of consolidated interest expense for such period, (b) the aggregate amount of income, franchise, capital or similar tax expense (other than ad valorem taxes) for such period, (c) all amounts attributable to depletion, depreciation, amortization and asset or goodwill impairment or writedown for such period, (d) all other non-cash charges, (e) exploration costs deducted in determining net income under successful efforts accounting, (f) actual cash distributions received from minority investments, (g) to the extent actually reimbursed by insurance, expenses with respect to liability on casualty events or business interruption, and (h) all reasonable transaction expenses related to dispositions and acquisitions of assets, investments and debt and equity offerings (provided that expenses related to any unsuccessful disposition will be limited to $3.0 million in the aggregate) for a twelve-month period may not be greater than 3.50 to 1.00; for the period December 31, 2014 through June 30, 2015 and 3.25 to 1.00 for the twelve-month period ending September 30, 2015 and periods thereafter; and
	(ii) the ratio of EBITDAX to interest expense for a twelve-month period may not be less than 3.00 to 1.00.
	The Company was in compliance with all covenants at March 31, 2015.
	(2) In March 2011, the Company entered into a new building loan agreement for the office building it occupies in Oklahoma City, Oklahoma. The new loan agreement refinanced the $2.4 million outstanding under the previous building loan agreement. The new agreement matures in February 2016 and bears interest at the rate of 5.82% per annum. The new building loan requires monthly interest and principal payments of approximately $22,000 and is collateralized by the Oklahoma City office building and associated land.
	(3) On October 17, 2012, the Company issued $250.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "October Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act (the "October Notes Offering") under an indenture among the Company, its subsidiary guarantors and Wells Fargo Bank, National Association, as the trustee (the "senior note indenture"). On December 21, 2012, the Company issued an additional $50.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "December Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the December Notes Offering"). The December Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the October Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of the October Notes Offering and the net proceeds of the December Notes Offering for general corporate purposes, which included funding a portion of its 2013 capital development plan. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act in October 2013 (the "Exchange Notes").
	On August 18, 2014, the Company issued an additional $300.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "August Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the August Notes Offering"). The August Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the August Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company intends to use the remaining net proceeds of the August Notes Offering for general corporate purposes, including funding a portion of its 2014 and 2015 capital development plans. The October Notes Offering, December Notes Offering and the August Notes Offering are collectively referred to as the "Notes Offerings" and the Exchange Notes, and the August Notes are collectively referred to as the "Old Notes".
	In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Notes was completed in March 2015.
	Under the senior note indenture relating to the Old Notes, interest on the Old Notes accrues at a rate of 7.75% per annum on the outstanding principal amount from October 17, 2012, payable semi-annually on May 1 and November 1 of each year, commencing on May 1, 2013. The Old Notes are the Company's senior unsecured obligations and rank equally in the right of payment with all of the Company's other senior indebtedness and senior in right of payment to any future subordinated indebtedness. All of the Company's existing and future restricted subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt guarantee the Old Notes; provided, however, that the Old Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company's future unrestricted subsidiaries. The Company may redeem some or all of the Old Notes at any time on or after November 1, 2016, at the redemption prices listed in the senior note indenture. Prior to November 1, 2016, the Company may redeem the Old Notes at a price equal to 100% of the principal amount plus a “make-whole” premium. In addition, prior to November 1, 2015, the Company may redeem up to 35% of the aggregate principal amount of the Old Notes with the net proceeds of certain equity offerings, provided that at least 65% of the aggregate principal amount of the Old Notes initially issued remains outstanding immediately after such redemption.
	(4) The October Notes were issued at a price of 98.534% resulting in a gross discount of $3.7 million and an effective rate of 8.000%. The December Notes were issued at a price of 101.000% resulting in a gross premium of $0.5 million and an effective rate of 7.531%. The August Notes were issued at a price of 106.000% resulting in a gross premium of $18.0 million and an effective rate of 6.561%. The premium and discount are being amortized using the effective interest method.
	(5) Does not reflect the Company's issuance of $350.0 million in aggregate principal amount of 6.625% Senior Notes due 2023 on April 21, 2015. See Note 14 - "Subsequent Events" below.

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2015
Share-based Compensation [Abstract]
Summary Of Stock Option Activity	A summary of the status of stock options and related activity for the three months ended March 31, 2015 is presented below:
		Shares		Weighted			Weighted		Aggregate
				Average			Average		Intrinsic
				Exercise Price			Remaining		Value (In thousands)
				per Share			Contractual Term
	Options outstanding at December 31, 2014	5,000		$	9.07		0.69		$	163
	Granted	—		—
	Exercised	—		—					—
	Forfeited/expired	—		—
	Options outstanding at March 31, 2015	5,000		$	9.07		0.44		$	184
	Options exercisable at March 31, 2015	5,000		$	9.07		0.44		$	184
Summary Of Stock Option Plans By Exercise Price	The following table summarizes information about the stock options outstanding at March 31, 2015:
	Exercise			Number		Weighted Average		Number
	Price			Outstanding		Remaining Life		Exercisable
						(in years)
	$	9.07		5,000		0.44		5,000
				5,000				5,000
Summary Of Restricted Stock Award And Unit Activity	The following table summarizes restricted stock activity for the three months ended March 31, 2015:
		Number of		Weighted
		Unvested		Average
		Restricted Shares		Grant Date
				Fair Value
	Unvested shares as of December 31, 2014	387,245		$	55.87
	Granted	100,226		44.04
	Vested	(60,381	)	52.94
	Forfeited	—		—
	Unvested shares as of March 31, 2015	427,090		$	53.51

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Schedule of Earnings Per Share Reconciliation	Reconciliations of the components of basic and diluted net income per common share are presented in the tables below:
		Three months ended March 31,
		2015					2014
		Income		Shares	Per		Income		Shares	Per
					Share					Share
		(In thousands, except share data)
	Basic:
	Net income	$	25,519	85,679,606	$	0.3	$	82,558	85,259,407	$	0.97
	Effect of dilutive securities:
	Stock options and awards	—		440,424			—		479,219
	Diluted:
	Net income	$	25,519	86,120,030	$	0.3	$	82,558	85,738,626	$	0.96

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Commitments	Future minimum lease commitments under these leases at March 31, 2015 were as follows:
		(In thousands)
	Remaining 2015	$	450
	2016	524
	2017	451
	2018	20
	2019	—
	Total	$	1,445
Schedule of Future Commitment Payments	Future minimum commitments under these agreements at March 31, 2015 are as follows:
		(In thousands)
	Remaining 2015	$	39,330
	2016	52,440
	2017	52,440
	2018	39,330
	Total	$	183,540

Hedging_Activities_Tables

Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2015
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Schedule Of Derivative Instruments	At March 31, 2015, the Company had the following fixed price swaps in place:
		Daily Volume		Weighted
		(Bbls/day)		Average Price
	April 2015 - June 2016	1,000		$	62.25
		Daily Volume (MMBtu/day)		Weighted
				Average Price
	Apr-15	191,250		$	4.05
	May 2015 - June 2015	201,250		$	4.05
	July 2015 - August 2015	216,875		$	4.04
	Sep-15	246,875		$	3.97
	October 2015 - December 2015	262,500		$	3.96
	January 2016 - March 2016	252,500		$	3.82
	Apr-16	242,500		$	3.81
	May 2016 - December 2016	172,500		$	3.73
	January 2017 - June 2017	142,500		$	3.67
	July 2017 - December 2017	80,000		$	3.45
	January 2018 - December 2018	30,000		$	3.4
	In addition, the Company has entered into natural gas basis swap positions, which settle on the pricing index to basis differential of MichCon to the NYMEX Henry Hub natural gas price. As of March 31, 2015, the Company's natural gas basis swap positions were as follows:
		Daily Volume (MMBtu/day)		Hedged Differential
	April 2015 - December 2016	30,000		$	0.02
	April 2015 - December 2016	10,000		$	0.01
Schedule Of Derivative Instruments In Statement Of Financial Position	At March 31, 2015 the fair value of derivative assets and liabilities related to the fixed price swaps and basis swaps was as follows:
		(In thousands)
	Short-term derivative instruments - asset	$	93,030
	Long-term derivative instruments - asset	$	41,956
	Short-term derivative instruments - liability	$	823

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	The following tables summarize the Company’s financial and non-financial liabilities by FASB ASC 820 valuation level as of March 31, 2015:
		March 31, 2015
		Level 1		Level 2		Level 3
		(In thousands)
	Assets:
	Fixed price swaps	$	134,986	$	—	$	—
	Liabilities:
	Fixed price swaps	$	823	$	—	$	—

Condensed_Consolidating_Financ1

Condensed Consolidating Financial Information (Tables)	3 Months Ended
	Mar. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Consolidating Balance Sheets	CONDENSED CONSOLIDATING BALANCE SHEETS
	(Amounts in thousands)
		March 31, 2015
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Assets
	Current assets:
	Cash and cash equivalents	$	73,667		$	1,072		$	1		$	—		$	74,740
	Accounts receivable - oil and gas	79,621			59			—			—			79,680
	Accounts receivable - related parties	33			—			—			—			33
	Accounts receivable - intercompany	48,154			26			—			(48,180		)	—
	Prepaid expenses and other current assets	15,777			—			—			—			15,777
	Short-term derivative instruments	93,030			—			—			—			93,030
	Total current assets	310,282			1,157			1			(48,180		)	263,260
	Property and equipment:
	Oil and natural gas properties, full-cost accounting	4,139,903			38,769			—			(710		)	4,177,962
	Other property and equipment	19,008			43			—			—			19,051
	Accumulated depletion, depreciation, amortization and impairment	(1,140,142		)	(26		)	—			—			(1,140,168		)
	Property and equipment, net	3,018,769			38,786			—			(710		)	3,056,845
	Other assets:
	Equity investments and investments in subsidiaries	365,840			—			167,186			(158,055		)	374,971
	Derivative instruments	41,956			—			—			—			41,956
	Other assets	18,566			—			—			—			18,566
	Total other assets	426,362			—			167,186			(158,055		)	435,493
	Total assets	$	3,755,413		$	39,943		$	167,187		$	(206,945	)	$	3,755,598
	Liabilities and Stockholders' Equity
	Current liabilities:
	Accounts payable and accrued liabilities	$	399,912		$	184		$	—		$	—		$	400,096
	Accounts payable - intercompany	—			48,072			108			(48,180		)	—
	Asset retirement obligation - current	75			—			—			—			75
	Short-term derivative instruments	823			—			—			—			823
	Deferred tax liability - current	29,622			—			—			—			29,622
	Current maturities of long-term debt	1,781			—			—			—			1,781
	Total current liabilities	432,213			48,256			108			(48,180		)	432,397
	Long-term derivative instrument	—			—			—			—			—
	Asset retirement obligation - long-term	18,656			—			—			—			18,656
	Deferred tax liability	215,122			—			—			—			215,122
	Long-term debt, net of current maturities	779,130			—			—			—			779,130
	Total liabilities	1,445,121			48,256			108			(48,180		)	1,445,305
	Stockholders' equity:
	Common stock	857			—			—			—			857
	Paid-in capital	1,832,062			321			233,174			(233,494		)	1,832,063
	Accumulated other comprehensive income (loss)	(41,659		)	—			(41,659		)	41,659			(41,659		)
	Retained earnings (accumulated deficit)	519,032			(8,634		)	(24,436		)	33,070			519,032
	Total stockholders' equity	2,310,292			(8,313		)	167,079			(158,765		)	2,310,293
	Total liabilities and stockholders' equity	$	3,755,413		$	39,943		$	167,187		$	(206,945	)	$	3,755,598
	CONDENSED CONSOLIDATING BALANCE SHEETS
	(Amounts in thousands)
		December 31, 2014
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Assets
	Current assets:
	Cash and cash equivalents	$	141,535		$	804		$	1		$	—		$	142,340
	Accounts receivable - oil and gas	103,762			96			—			—			103,858
	Accounts receivable - related parties	46			—			—			—			46
	Accounts receivable - intercompany	45,222			27			—			(45,249		)	—
	Prepaid expenses and other current assets	3,714			—			—			—			3,714
	Short-term derivative instruments	78,391			—			—			—			78,391
	Total current assets	372,670			927			1			(45,249		)	328,349
	Property and equipment:
	Oil and natural gas properties, full-cost accounting,	3,887,874			35,990			—			(710		)	3,923,154
	Other property and equipment	18,301			43			—			—			18,344
	Accumulated depletion, depreciation, amortization and impairment	(1,050,855		)	(24		)	—			—			(1,050,879		)
	Property and equipment, net	2,855,320			36,009			—			(710		)	2,890,619
	Other assets:
Equity investments and investments in subsidiaries	360,238			—			180,217			(170,874		)	369,581
Derivative instruments	24,448			—			—			—			24,448
Other assets	19,396			—			—			—			19,396
Total other assets	404,082			—			180,217			(170,874		)	413,425
Total assets	$	3,632,072		$	36,936		$	180,218		$	(216,833	)	$	3,632,393
Liabilities and Stockholders' Equity
Current liabilities:
Accounts payable and accrued liabilities	$	371,089		$	321		$	—		$	—		$	371,410
Accounts payable - intercompany	—			45,143			106			(45,249		)	—
Asset retirement obligation - current	75			—			—			—			75
Deferred tax liability	27,070			—			—			—			27,070
Current maturities of long-term debt	168			—			—			—			168
Total current liabilities	398,402			45,464			106			(45,249		)	398,723
Asset retirement obligation - long-term	17,863			—			—			—			17,863
Deferred tax liability	203,195			—			—			—			203,195
Long-term debt, net of current maturities	716,316			—			—			—			716,316
Total liabilities	1,335,776			45,464			106			(45,249		)	1,336,097
Stockholders' equity:
Common stock	856			—			—			—			856
Paid-in capital	1,828,602			322			227,079			(227,401		)	1,828,602
Accumulated other comprehensive income (loss)	(26,675		)	—			(26,675		)	26,675			(26,675		)
Retained earnings (accumulated deficit)	493,513			(8,850		)	(20,292		)	29,142			493,513
Total stockholders' equity	2,296,296			(8,528		)	180,112			(171,584		)	2,296,296
Total liabilities and stockholders' equity	$	3,632,072		$	36,936		$	180,218		$	(216,833	)	$	3,632,393
Condensed Consolidating Statements of Operations	CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
	(Amounts in thousands)
		Three months ended March 31, 2015
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Total revenues	$	175,832		$	485		$	—		$	—		$	176,317
	Costs and expenses:
	Lease operating expenses	16,787			193			—			—			16,980
	Production taxes	4,253			32			—			—			4,285
	Midstream gathering and processing	25,374			7			—			—			25,381
	Depreciation, depletion, and amortization	89,908			1			—			—			89,909
	General and administrative	10,761			36			2			—			10,799
	Accretion expense	190			—			—			—			190
		147,273			269			2			—			147,544
	INCOME FROM OPERATIONS	28,559			216			(2		)	—			28,773
	OTHER (INCOME) EXPENSE:
	Interest expense	8,759			—			—			—			8,759
	Interest income	(9		)	—			—			—			(9		)
	(Income) loss from equity method investments and investments in subsidiaries	(20,189		)	—			4,142			(3,928		)	(19,975		)
		(11,439		)	—			4,142			(3,928		)	(11,225		)
	INCOME (LOSS) BEFORE INCOME TAXES	39,998			216			(4,144		)	3,928			39,998
	INCOME TAX EXPENSE	14,479			—			—			—			14,479
	NET INCOME (LOSS)	$	25,519		$	216		$	(4,144	)	$	3,928		$	25,519
	CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
	(Amounts in thousands)
		Three months ended March 31, 2014
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Total revenues	$	117,850		$	179		$	—		$	—		$	118,029
	Costs and expenses:
	Lease operating expenses	11,381			248			—			—			11,629
	Production taxes	6,937			20			—			—			6,957
	Midstream gathering and processing	7,757			12			—			—			7,769
	Depreciation, depletion, and amortization	56,877			—			—			—			56,877
	General and administrative	9,488			27			(4		)	—			9,511
	Accretion expense	188			—			—			—			188
	Gain on sale of assets	(11		)	—			—			—			(11		)
		92,617			307			(4		)	—			92,920
	INCOME (LOSS) FROM OPERATIONS	25,233			(128		)	4			—			25,109
	OTHER (INCOME) EXPENSE:
	Interest expense	3,885			—			—			—			3,885
	Interest income	(106		)	—			—			—			(106		)
	Litigation settlement	18,000			—			—			—			18,000
	(Income) loss from equity method investments and investments in subsidiaries	(128,351		)	—			2,001			(2,125		)	(128,475		)
		(106,572		)	—			2,001			(2,125		)	(106,696		)
	INCOME (LOSS) BEFORE INCOME TAXES	131,805			(128		)	(1,997		)	2,125			131,805
	INCOME TAX EXPENSE	49,247			—			—			—			49,247
	NET INCOME (LOSS)	$	82,558		$	(128	)	$	(1,997	)	$	2,125		$	82,558
Condensed Consolidating Statements of Comprehensive Income (Loss)
		Three months ended March 31, 2015
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Net income (loss)	$	25,519		$	216		$	(4,144	)	$	3,928		$	25,519
	Foreign currency translation adjustment	(14,984		)	—			(14,984		)	14,984			(14,984		)
	Other comprehensive income (loss)	(14,984		)	—			(14,984		)	14,984			(14,984		)
	Comprehensive income (loss)	$	10,535		$	216		$	(19,128	)	$	18,912		$	10,535
		Three months ended March 31, 2014
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Net income (loss)	$	82,558		$	(128	)	$	(1,997	)	$	2,125		$	82,558
	Foreign currency translation adjustment	(7,278		)	—			(7,278		)	7,278			(7,278		)
	Other comprehensive income (loss)	(7,278		)	—			(7,278		)	7,278			(7,278		)
	Comprehensive income (loss)	$	75,280		$	(128	)	$	(9,275	)	$	9,403		$	75,280
Condensed Consolidating Statements of Cash Flows
		Three months ended March 31, 2015
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Net cash provided by operating activities	$	95,879		$	3,158		$	—		$	—		$	99,037
	Net cash provided by (used in) investing activities	(228,601		)	(2,890		)	(6,093		)	6,093			(231,491		)
	Net cash provided by (used in) financing activities	64,854			—			6,093			(6,093		)	64,854
	Net (decrease) increase in cash and cash equivalents	(67,868		)	268			—			—			(67,600		)
	Cash and cash equivalents at beginning of period	141,535			804			1			—			142,340
	Cash and cash equivalents at end of period	$	73,667		$	1,072		$	1		$	—		$	74,740
		Three months ended March 31, 2014
		Parent			Guarantors			Non-Guarantor			Eliminations			Consolidated
	Net cash provided by (used in) operating activities	$	159,736		$	(3,585	)	$	(1	)	$	—		$	156,150
	Net cash provided by (used in) investing activities	(443,079		)	(2,034		)	(8,069		)	8,070			(445,112		)
	Net cash provided by (used in) financing activities	388			—			8,070			(8,070		)	388
	Net decrease in cash and cash equivalents	(282,955		)	(5,619		)	—			—			(288,574		)
	Cash and cash equivalents at beginning of period	451,431			7,525			—			—			458,956
	Cash and cash equivalents at end of period	$	168,476		$	1,906		$	—		$	—		$	170,382

Acquisitions_Details

Acquisitions (Details) (USD $)	3 Months Ended		0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 20, 2014	Feb. 28, 2014
				acre
Business Acquisition [Line Items]
Net revenues	$176,317,000	$118,029,000
Lease operating expenses	16,980,000	11,629,000
Utica Shale [Member]
Business Acquisition [Line Items]
Gas and oil acreage, undeveloped, net				8,000
Purchase price			182,000,000
Cash, net of purchase price adjustments			179,527,000
Fair value of net identifiable assets acquired			179,527,000
Utica Shale [Member] | Proved Properties [Member]
Business Acquisition [Line Items]
Fair value of net identifiable assets acquired			31,961,000
Utica Shale [Member] | Unproved Properties [Member]
Business Acquisition [Line Items]
Fair value of net identifiable assets acquired			6,263,000
Utica Shale [Member] | Unevaluated Properties [Member]
Business Acquisition [Line Items]
Fair value of net identifiable assets acquired			$141,303,000

Property_And_Equipment_Schedul

Property And Equipment (Schedule Of Property And Equipment) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment [Abstract]
Oil and natural gas properties	$4,177,962	$3,923,154
Office furniture and fixtures	11,133	10,752
Building	5,724	5,398
Land	2,194	2,194
Total property and equipment	4,197,013	3,941,498
Accumulated depletion, depreciation, amortization and impairment	-1,140,168	-1,050,879
Property and equipment, net	$3,056,845	$2,890,619

Property_And_Equipment_Narrati

Property And Equipment (Narrative) (Details) (USD $)	3 Months Ended		1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Jan. 31, 2013	Dec. 31, 2014	Oct. 31, 2012	Oct. 11, 2012	7-May-12
Property, Plant and Equipment [Line Items]
Cumulative capitalization of general and administrative costs incurred and capitalized to the full cost pool	$79,900,000
Capitalized general and administrative costs	7,200,000	6,300,000
Capitalized costs of oil and natural gas properties excluded from amortization	1,546,804,000			1,465,538,000
Payment received from Diamondback	-24,178,000	27,944,000
Diamondback [Member]
Property, Plant and Equipment [Line Items]
Investment (shares)						7,914,036
Promissory note receivable						63,600,000
Ownership interest					21.40%		35.00%
Diamondback [Member] | Accounts Receivable - Related Party [Member]
Property, Plant and Equipment [Line Items]
Payment received from Diamondback			$18,600,000
Minimum [Member]
Property, Plant and Equipment [Line Items]
Expected number of years amortization will commence	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Expected number of years amortization will commence	5 years

Property_And_Equipment_Summary

Property And Equipment (Summary Of Oil And Gas Properties Not Subject To Amortization) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total oil and gas properties not subject to amortization, total	$1,546,804	$1,465,538
Colorado [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total oil and gas properties not subject to amortization, total	5,088
Bakken [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total oil and gas properties not subject to amortization, total	96
Southern Louisiana [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total oil and gas properties not subject to amortization, total	283
Ohio [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total oil and gas properties not subject to amortization, total	1,541,292
Other [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total oil and gas properties not subject to amortization, total	$45

Property_And_Equipment_Schedul1

Property And Equipment (Schedule Of Asset Retirement Obligation) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation, beginning of period	$17,938	$15,083
Liabilities incurred	1,584	1,869
Liabilities settled	-981	-1,695
Accretion expense	190	188
Asset retirement obligation as of end of period	18,731	15,445
Less current portion	75	795	75
Asset retirement obligation, long-term	$18,656	$14,650	$17,863

Equity_Investments_Investments

Equity Investments (Investments Accounted For By The Equity Method) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Oct. 11, 2012
Schedule of Equity Method Investments [Line Items]
Equity investments and investments in subsidiaries	$374,971		$369,581
(Income) loss from equity method investments	-19,975	-128,475
Tatex Thailand II, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	23.50%
(Income) loss from equity method investments	0	0
Tatex Thailand III, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	17.90%
Equity investments and investments in subsidiaries	0
(Income) loss from equity method investments	0	49
Grizzly Oil Sands ULC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	25.00%
Equity investments and investments in subsidiaries	167,186		180,218
(Income) loss from equity method investments	4,142	2,001
Bison Drilling And Field Services LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	0.00%
(Income) loss from equity method investments	0	1,933
Muskie Proppant LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	0.00%
(Income) loss from equity method investments	0	534
Timber Wolf Terminals LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	50.00%
Equity investments and investments in subsidiaries	1,007		1,013
(Income) loss from equity method investments	6	0
Windsor Midstream LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	22.50%
Equity investments and investments in subsidiaries	32,292		13,505
(Income) loss from equity method investments	-18,787	-168
Stingray Pressure Pumping LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	0.00%
(Income) loss from equity method investments	0	513
Stingray Cementing LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	50.00%
Equity investments and investments in subsidiaries	2,254		2,647
(Income) loss from equity method investments	67	95
Blackhawk Midstream LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	48.50%
Equity investments and investments in subsidiaries	0		0
(Income) loss from equity method investments	-7,217	-84,787
Stingray Logistics LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	0.00%
Equity investments and investments in subsidiaries	0		0
(Income) loss from equity method investments	0	81
Diamondback Energy, Inc [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	0.00%
Equity investments and investments in subsidiaries	0		0	138,500
(Income) loss from equity method investments	0	-48,767
Stingray Energy Services LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	50.00%
Equity investments and investments in subsidiaries	6,167		5,718
(Income) loss from equity method investments	10	41
Sturgeon Acquisitions LLC [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	25.00%		25.00%
Equity investments and investments in subsidiaries	22,258		22,507
(Income) loss from equity method investments	-568	0
Mammoth Energy Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Approximate Ownership %	30.50%		30.50%
Equity investments and investments in subsidiaries	143,807		143,973
(Income) loss from equity method investments	$2,372	$0

Equity_Investments_Equity_Inve

Equity Investments (Equity Investments Balance Sheet Disclosure) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Equity Method Investments and Joint Ventures [Abstract]
Current assets	$151,752	$181,060
Noncurrent assets	1,419,656	1,306,891
Current liabilities	55,369	114,506
Noncurrent liabilities	$213,050	$230,062

Equity_Investments_Equity_Inve1

Equity Investments (Equity Investment Income Statement Disclosure) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Gross revenue	$133,556	$158,281
Net income	$90,668	$181,505

Equity_Investments_Narrative_D

Equity Investments (Narrative) (Details) (USD $)	3 Months Ended		1 Months Ended	0 Months Ended		1 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Jan. 28, 2014	Nov. 12, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2012	Oct. 11, 2012
Schedule of Equity Method Investments [Line Items]
Payments for equity method investments	$6,093,000	$23,687,000
Equity investments and investments in subsidiaries	374,971,000		374,971,000						369,581,000
(Income) loss from equity method investments	-19,975,000	-128,475,000
Distributions received	817,000	0
Apico Llc [Member]
Schedule of Equity Method Investments [Line Items]
Equity shares owned by affiliate (shares)	85,122
Total shares owned of subaffiliate (shares)	1,000,000
Gas and oil area, reserve (acres)	243,000
Tatex Thailand III, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Gas and oil area, reserve (acres)	245,000
Ownership interest	17.90%		17.90%
Equity investments and investments in subsidiaries	0		0
(Income) loss from equity method investments	0	49,000
Grizzly Oil Sands ULC [Member]
Schedule of Equity Method Investments [Line Items]
Gas and oil area, reserve (acres)	830,000
Cash calls paid	6,100,000
Increase (decrease) due to foreign currency translation adjustment	15,000,000	7,300,000
Ownership interest	25.00%		25.00%
Equity investments and investments in subsidiaries	167,186,000		167,186,000						180,218,000
(Income) loss from equity method investments	4,142,000	2,001,000
Windsor Midstream LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	22.50%		22.50%
Equity investments and investments in subsidiaries	32,292,000		32,292,000						13,505,000
(Income) loss from equity method investments	-18,787,000	-168,000
Windsor Midstream LLC [Member] | MidMar Gas LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest										28.40%
Coronado Midstream [Member] | Windsor Midstream LLC [Member]
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of interest in partnership unit			600,000,000
Gain on sale on investment			85,500,000
Blackhawk Midstream LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	48.50%		48.50%
Equity investments and investments in subsidiaries	0		0						0
(Income) loss from equity method investments	-7,217,000	-84,787,000
Blackhawk Midstream LLC [Member] | Ohio Gathering Company, LLC and Ohio Condensate Company, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Purchase price of sold equity interests				190,000,000
Amount put in escrow				14,300,000
Proceeds from release of escrow deposits	7,200,000
Distributions received		84,800,000
Diamondback Energy, Inc [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	0.00%		0.00%
Investment (shares)											7,914,036
Equity investments and investments in subsidiaries	0		0						0		138,500,000
Number of shares issued in transaction (shares)					942,000	1,437,500	1,000,000	4,534,536
Proceeds received from sale of stock					60,800,000	197,600,000		192,700,000
(Income) loss from equity method investments	0	-48,767,000
Sturgeon Acquisitions LLC [Member]
Schedule of Equity Method Investments [Line Items]
Payments for equity method investments									20,700,000
Ownership interest	25.00%		25.00%						25.00%
Equity investments and investments in subsidiaries	22,258,000		22,258,000						22,507,000
(Income) loss from equity method investments	-568,000	0
Distributions received	800,000
Mammoth Energy Partners LP [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest	30.50%		30.50%						30.50%
Equity investments and investments in subsidiaries	143,807,000		143,807,000						143,973,000
(Income) loss from equity method investments	2,372,000	0
Equity investment in Mammoth Energy Partners									$143,500,000

Other_Assets_Schedule_Of_Other

Other Assets (Schedule Of Other Assets) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Schedule of Prepaid Expenses [Line Items]
Plugging and abandonment escrow account on the WCBB properties (Note 8)	$3,089,000	$3,097,000
Certificates of Deposit securing letter of credit	275,000	275,000
Prepaid drilling costs	269,000	483,000
Loan commitment fees	14,771,000	15,390,000
Deposits	34,000	34,000
Other	128,000	117,000
Other assets	18,566,000	19,396,000
Prepaid Expenses and Other Current Assets [Member]
Schedule of Prepaid Expenses [Line Items]
Prepaid taxes	12,100,000
Prepaid insurance	2,300,000
Prepaid other expenses	$1,400,000

LongTerm_Debt_BreakDown_Of_Lon

Long-Term Debt (Break-Down Of Long-Term Debt) (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014		Mar. 31, 2011	Aug. 18, 2014	Dec. 21, 2012	Oct. 17, 2012
Debt Instrument [Line Items]
Unamortized original issue (discount) premium, net (4)	$14,130,000	[1]	$14,658,000	[1]
Less: current maturities of long term debt	-1,781,000		-168,000
Long-term debt, net of current maturities	779,130,000		716,316,000
Line of Credit [Member]
Debt Instrument [Line Items]
Long-term debt	165,000,000	[2]	100,000,000	[2]
Building loans [Member]
Debt Instrument [Line Items]
Long-term debt	1,781,000	[3]	1,826,000	[3]	2,400,000
7.75% senior unsecured notes due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt	$600,000,000	[4]	$600,000,000	[4]		$600,000,000	$600,000,000	$600,000,000
[1]	The October Notes were issued at a price of 98.534% resulting in a gross discount of $3.7 million and an effective rate of 8.000%. The December Notes were issued at a price of 101.000% resulting in a gross premium of $0.5 million and an effective rate of 7.531%. The August Notes were issued at a price of 106.000% resulting in a gross premium of $18.0 million and an effective rate of 6.561%. The premium and discount are being amortized using the effective interest method.
[2]	On December 27, 2013, the Company entered into an Amended and Restated Credit Agreement with The Bank of Nova Scotia, as administrative agent, sole lead arranger and sole bookrunner, Amegy Bank National Association, as syndication agent, KeyBank National Association, as documentation agent, and other lenders (The "Amended and Restated Credit Agreement") that provides for a maximum facility amount of $1.5 billion. The Amended and Restated Credit Agreement matures on June 6, 2018. The Company’s wholly-owned subsidiaries have guaranteed the obligations of the Company under the Amended and Restated Credit Agreement. On April 23, 2014, the Company entered into a first amendment to the Amended and Restated Credit Agreement. The first amendment increased the letter of credit sublimit from $20.0 million to $70.0 million and provided for an increase in the borrowing base availability from $150.0 million to $275.0 million. The first amendment also made certain changes to the lenders and their respective lending commitments thereunder. On November 26, 2014, the Company entered into a second amendment to the Amended and Restated Credit Agreement. The second amendment changed the definition of EBITDAX to exclude proceeds from the disposition of equity method investments and changed the ratio of funded debt to EBITDAX to be the ratio of net funded debt to EBITDAX. Net funded debt is funded debt less the amount of cash and short-term investments the Company has at the end of the relevant fiscal quarter. The second amendment increases the ratio from 2.00 to 1.00 to 3.50 to 1.00 for the period December 31, 2014 through June 30, 2015 and then decreases the ratio to 3.25 to 1.00 for the periods thereafter. Further, the second amendment increased the letter of credit sublimit from $70.0 million to $125.0 million and provided for an increase in the borrowing base availability from $275.0 million to $450.0 million. As of March 31, 2015, $165.0 million was outstanding under the Amended and Restated Credit Agreement. At March 31, 2015, the total availability for future borrowings under the Amended and Restated Credit Agreement, after giving effect to an aggregate of $68.2 million of letters of credit, was $216.8 million.On April 10, 2015, the Company entered into a third amendment to the Amended and Restated Credit Agreement. The third amendment increased the borrowing base from $450.0 million to $575.0 million and increased the Company's basket for unsecured debt issuances to $1.2 billion. The third amendment also made certain changes to the lenders and their respective lending commitments thereunder.Advances under the Amended and Restated Credit Agreement may be in the form of either base rate loans or eurodollar loans. The interest rate for base rate loans is equal to (1) the applicable rate, which ranges from 0.50% to 1.50%, plus (2) the highest of: (a) the federal funds rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by agent as its “prime rate,” and (c) the eurodollar rate for an interest period of one month plus 1.00%. The interest rate for eurodollar loans is equal to (1) the applicable rate, which ranges from 1.50% to 2.50%, plus (2) the London interbank offered rate that appears on pages LIBOR01 or LIBOR02 of the Reuters screen that displays such rate for deposits in U.S. dollars, or, if such rate is not available, the rate as administered by ICE Benchmark Administration (or any other person that takes over administration of such rate) per annum equal to the offered rate on such other page or service that displays on average London interbank offered rate as determined by ICE Benchmark Administration (or any other person that takes over administration of such rate) for deposits in U.S. dollars, or, if such rate is not available, the average quotations for three major New York money center banks of whom the agent shall inquire as the “London Interbank Offered Rate” for deposits in U.S. dollars. At March 31, 2015, amounts borrowed under the Amended and Restated Credit Agreement bore interest at the Eurodollar rate (2.18%).The Amended and Restated Credit Agreement contains customary negative covenants including, but not limited to, restrictions on the Company’s and its subsidiaries’ ability to: •incur indebtedness; •grant liens; •pay dividends and make other restricted payments; •make investments; •make fundamental changes; •enter into swap contracts and forward sales contracts; •dispose of assets; •change the nature of their business; and •enter into transactions with affiliates. The negative covenants are subject to certain exceptions as specified in the Amended and Restated Credit Agreement. The Amended and Restated Credit Agreement also contains certain affirmative covenants, including, but not limited to the following financial covenants: (i) the ratio of net funded debt to EBITDAX (net income, excluding (i) any non-cash revenue or expense associated with swap contracts resulting from ASC 815 and (ii) any cash or noncash revenue or expense attributable to minority investments plus without duplication and, in the case of expenses, to the extent deducted from revenues in determining net income, the sum of (a) the aggregate amount of consolidated interest expense for such period, (b) the aggregate amount of income, franchise, capital or similar tax expense (other than ad valorem taxes) for such period, (c) all amounts attributable to depletion, depreciation, amortization and asset or goodwill impairment or writedown for such period, (d) all other non-cash charges, (e) exploration costs deducted in determining net income under successful efforts accounting, (f) actual cash distributions received from minority investments, (g) to the extent actually reimbursed by insurance, expenses with respect to liability on casualty events or business interruption, and (h) all reasonable transaction expenses related to dispositions and acquisitions of assets, investments and debt and equity offerings (provided that expenses related to any unsuccessful disposition will be limited to $3.0 million in the aggregate) for a twelve-month period may not be greater than 3.50 to 1.00; for the period December 31, 2014 through June 30, 2015 and 3.25 to 1.00 for the twelve-month period ending September 30, 2015 and periods thereafter; and (ii) the ratio of EBITDAX to interest expense for a twelve-month period may not be less than 3.00 to 1.00. The Company was in compliance with all covenants at March 31, 2015.
[3]	In March 2011, the Company entered into a new building loan agreement for the office building it occupies in Oklahoma City, Oklahoma. The new loan agreement refinanced the $2.4 million outstanding under the previous building loan agreement. The new agreement matures in February 2016 and bears interest at the rate of 5.82% per annum. The new building loan requires monthly interest and principal payments of approximately $22,000 and is collateralized by the Oklahoma City office building and associated land.
[4]	On October 17, 2012, the Company issued $250.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "October Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act (the "October Notes Offering") under an indenture among the Company, its subsidiary guarantors and Wells Fargo Bank, National Association, as the trustee (the "senior note indenture"). On December 21, 2012, the Company issued an additional $50.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "December Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the December Notes Offering"). The December Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the October Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of the October Notes Offering and the net proceeds of the December Notes Offering for general corporate purposes, which included funding a portion of its 2013 capital development plan. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act in October 2013 (the "Exchange Notes").On August 18, 2014, the Company issued an additional $300.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "August Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the August Notes Offering"). The August Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the August Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company intends to use the remaining net proceeds of the August Notes Offering for general corporate purposes, including funding a portion of its 2014 and 2015 capital development plans. The October Notes Offering, December Notes Offering and the August Notes Offering are collectively referred to as the "Notes Offerings" and the Exchange Notes, and the August Notes are collectively referred to as the "Old Notes".In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Notes was completed in March 2015.Under the senior note indenture relating to the Old Notes, interest on the Old Notes accrues at a rate of 7.75% per annum on the outstanding principal amount from October 17, 2012, payable semi-annually on May 1 and November 1 of each year, commencing on May 1, 2013. The Old Notes are the Company's senior unsecured obligations and rank equally in the right of payment with all of the Company's other senior indebtedness and senior in right of payment to any future subordinated indebtedness. All of the Company's existing and future restricted subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt guarantee the Old Notes; provided, however, that the Old Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company's future unrestricted subsidiaries. The Company may redeem some or all of the Old Notes at any time on or after November 1, 2016, at the redemption prices listed in the senior note indenture. Prior to November 1, 2016, the Company may redeem the Old Notes at a price equal to 100% of the principal amount plus a “make-whole” premium. In addition, prior to November 1, 2015, the Company may redeem up to 35% of the aggregate principal amount of the Old Notes with the net proceeds of certain equity offerings, provided that at least 65% of the aggregate principal amount of the Old Notes initially issued remains outstanding immediately after such redemption.

LongTerm_Debt_Narrative_Detail

Long-Term Debt (Narrative) (Details) (USD $)

3 Months Ended

1 Months Ended

0 Months Ended

Mar. 31, 2015

Mar. 31, 2014

Mar. 31, 2011

Apr. 23, 2014

Dec. 31, 2014

Aug. 18, 2014

Dec. 21, 2012

Oct. 17, 2012

Apr. 16, 2015

Nov. 26, 2014

Apr. 22, 2014

Dec. 27, 2013

Apr. 10, 2015

Debt Instrument [Line Items]

Interest cost capitalized, undeveloped properties

$3,700,000

$2,300,000

Minimum [Member]

Debt Instrument [Line Items]

Debt covenant ratio for EBITDAX

3

Maximum [Member]

Debt Instrument [Line Items]

Debt covenant ratio for future EBITDAX

3.25

Debt covenant ratio for reasonable transactions

3.5

Building Loans [Member]

Debt Instrument [Line Items]

Building loan outstanding amount of building loan refinanced

1,781,000

[1]

2,400,000

1,826,000

[1]

Stated interest rate

5.82%

Loan, periodic payment

22,000

Senior Notes [Member]

Debt Instrument [Line Items]

Building loan outstanding amount of building loan refinanced

600,000,000

[2]

600,000,000

[2]

600,000,000

600,000,000

600,000,000

Effective interest rate

6.56%

7.53%

8.00%

Stated interest rate

7.75%

7.75%

7.75%

Debt issued

300,000,000

50,000,000

250,000,000

Redemption of principal amount plus aggregate net proceeds

100.00%

Discount issue price, price

98.53%

Unamortized discount

3,700,000

Premium issue price, percent

106.00%

101.00%

Unamortized premium

18,000,000

500,000

Senior Notes [Member] | Minimum [Member]

Debt Instrument [Line Items]

Percentage of notes required to be outstanding for redemption

65.00%

Senior Notes [Member] | Maximum [Member]

Debt Instrument [Line Items]

Redemption of principal amount plus aggregate net proceeds

35.00%

Notes Due 2023 [Member] | Senior Notes [Member] | Subsequent Event [Member]

Debt Instrument [Line Items]

Stated interest rate

6.63%

Debt instrument, amount

350,000,000

Nova Scotia, Amegy, KeyBank [Member]

Debt Instrument [Line Items]

Revolving credit facility

1,500,000,000

Borrowing capacity

275,000,000

450,000,000

150,000,000

Remaining borrowing capacity

216,800,000

Nova Scotia, Amegy, KeyBank [Member] | Subsequent Event [Member]

Debt Instrument [Line Items]

Borrowing capacity

575,000,000

Line of Credit Facility, Unsecured Debt Issuance Restriction

1,200,000,000

Nova Scotia, Amegy, KeyBank [Member] | Base Rate Loans [Member]

Debt Instrument [Line Items]

Applicable rate, minimum

0.50%

Applicable rate, maximum

1.50%

Nova Scotia, Amegy, KeyBank [Member] | Base Rate Loans [Member] | Federal Funds Rate [Member]

Debt Instrument [Line Items]

Basis spread

0.50%

Nova Scotia, Amegy, KeyBank [Member] | Base Rate Loans [Member] | Eurodollar [Member]

Debt Instrument [Line Items]

Basis spread

1.00%

Nova Scotia, Amegy, KeyBank [Member] | Euro Dollar Loans [Member]

Debt Instrument [Line Items]

Applicable rate, minimum

1.50%

Applicable rate, maximum

2.50%

Effective interest rate

2.18%

Nova Scotia, Amegy, KeyBank [Member] | Letter of Credit [Member]

Debt Instrument [Line Items]

Borrowing capacity

70,000,000

125,000,000

20,000,000

Debt covenant ratio for EBITDAX

2

Credit facility outstanding

68,200,000

[3]

Nova Scotia, Amegy, KeyBank [Member] | Letter of Credit [Member] | Second Amendment of Restated Credit Agreement [Member]

Debt Instrument [Line Items]

Debt covenant ratio for EBITDAX

3.5

Disposition costs, maximum expenses allowed

$3,000,000

Debt covenant ratio for future EBITDAX

3.25

[1]

In March 2011, the Company entered into a new building loan agreement for the office building it occupies in Oklahoma City, Oklahoma. The new loan agreement refinanced the $2.4 million outstanding under the previous building loan agreement. The new agreement matures in February 2016 and bears interest at the rate of 5.82% per annum. The new building loan requires monthly interest and principal payments of approximately $22,000 and is collateralized by the Oklahoma City office building and associated land.

[2]

On October 17, 2012, the Company issued $250.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "October Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act (the "October Notes Offering") under an indenture among the Company, its subsidiary guarantors and Wells Fargo Bank, National Association, as the trustee (the "senior note indenture"). On December 21, 2012, the Company issued an additional $50.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "December Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the December Notes Offering"). The December Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the October Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of the October Notes Offering and the net proceeds of the December Notes Offering for general corporate purposes, which included funding a portion of its 2013 capital development plan. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act in October 2013 (the "Exchange Notes").On August 18, 2014, the Company issued an additional $300.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "August Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the August Notes Offering"). The August Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the August Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company intends to use the remaining net proceeds of the August Notes Offering for general corporate purposes, including funding a portion of its 2014 and 2015 capital development plans. The October Notes Offering, December Notes Offering and the August Notes Offering are collectively referred to as the "Notes Offerings" and the Exchange Notes, and the August Notes are collectively referred to as the "Old Notes".In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Notes was completed in March 2015.Under the senior note indenture relating to the Old Notes, interest on the Old Notes accrues at a rate of 7.75% per annum on the outstanding principal amount from October 17, 2012, payable semi-annually on May 1 and November 1 of each year, commencing on May 1, 2013. The Old Notes are the Company's senior unsecured obligations and rank equally in the right of payment with all of the Company's other senior indebtedness and senior in right of payment to any future subordinated indebtedness. All of the Company's existing and future restricted subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt guarantee the Old Notes; provided, however, that the Old Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company's future unrestricted subsidiaries. The Company may redeem some or all of the Old Notes at any time on or after November 1, 2016, at the redemption prices listed in the senior note indenture. Prior to November 1, 2016, the Company may redeem the Old Notes at a price equal to 100% of the principal amount plus a “make-whole” premium. In addition, prior to November 1, 2015, the Company may redeem up to 35% of the aggregate principal amount of the Old Notes with the net proceeds of certain equity offerings, provided that at least 65% of the aggregate principal amount of the Old Notes initially issued remains outstanding immediately after such redemption.

[3]

On December 27, 2013, the Company entered into an Amended and Restated Credit Agreement with The Bank of Nova Scotia, as administrative agent, sole lead arranger and sole bookrunner, Amegy Bank National Association, as syndication agent, KeyBank National Association, as documentation agent, and other lenders (The "Amended and Restated Credit Agreement") that provides for a maximum facility amount of $1.5 billion. The Amended and Restated Credit Agreement matures on June 6, 2018. The Company’s wholly-owned subsidiaries have guaranteed the obligations of the Company under the Amended and Restated Credit Agreement. On April 23, 2014, the Company entered into a first amendment to the Amended and Restated Credit Agreement. The first amendment increased the letter of credit sublimit from $20.0 million to $70.0 million and provided for an increase in the borrowing base availability from $150.0 million to $275.0 million. The first amendment also made certain changes to the lenders and their respective lending commitments thereunder. On November 26, 2014, the Company entered into a second amendment to the Amended and Restated Credit Agreement. The second amendment changed the definition of EBITDAX to exclude proceeds from the disposition of equity method investments and changed the ratio of funded debt to EBITDAX to be the ratio of net funded debt to EBITDAX. Net funded debt is funded debt less the amount of cash and short-term investments the Company has at the end of the relevant fiscal quarter. The second amendment increases the ratio from 2.00 to 1.00 to 3.50 to 1.00 for the period December 31, 2014 through June 30, 2015 and then decreases the ratio to 3.25 to 1.00 for the periods thereafter. Further, the second amendment increased the letter of credit sublimit from $70.0 million to $125.0 million and provided for an increase in the borrowing base availability from $275.0 million to $450.0 million. As of March 31, 2015, $165.0 million was outstanding under the Amended and Restated Credit Agreement. At March 31, 2015, the total availability for future borrowings under the Amended and Restated Credit Agreement, after giving effect to an aggregate of $68.2 million of letters of credit, was $216.8 million.On April 10, 2015, the Company entered into a third amendment to the Amended and Restated Credit Agreement. The third amendment increased the borrowing base from $450.0 million to $575.0 million and increased the Company's basket for unsecured debt issuances to $1.2 billion. The third amendment also made certain changes to the lenders and their respective lending commitments thereunder.Advances under the Amended and Restated Credit Agreement may be in the form of either base rate loans or eurodollar loans. The interest rate for base rate loans is equal to (1) the applicable rate, which ranges from 0.50% to 1.50%, plus (2) the highest of: (a) the federal funds rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by agent as its “prime rate,” and (c) the eurodollar rate for an interest period of one month plus 1.00%. The interest rate for eurodollar loans is equal to (1) the applicable rate, which ranges from 1.50% to 2.50%, plus (2) the London interbank offered rate that appears on pages LIBOR01 or LIBOR02 of the Reuters screen that displays such rate for deposits in U.S. dollars, or, if such rate is not available, the rate as administered by ICE Benchmark Administration (or any other person that takes over administration of such rate) per annum equal to the offered rate on such other page or service that displays on average London interbank offered rate as determined by ICE Benchmark Administration (or any other person that takes over administration of such rate) for deposits in U.S. dollars, or, if such rate is not available, the average quotations for three major New York money center banks of whom the agent shall inquire as the “London Interbank Offered Rate” for deposits in U.S. dollars. At March 31, 2015, amounts borrowed under the Amended and Restated Credit Agreement bore interest at the Eurodollar rate (2.18%).The Amended and Restated Credit Agreement contains customary negative covenants including, but not limited to, restrictions on the Company’s and its subsidiaries’ ability to: •incur indebtedness; •grant liens; •pay dividends and make other restricted payments; •make investments; •make fundamental changes; •enter into swap contracts and forward sales contracts; •dispose of assets; •change the nature of their business; and •enter into transactions with affiliates. The negative covenants are subject to certain exceptions as specified in the Amended and Restated Credit Agreement. The Amended and Restated Credit Agreement also contains certain affirmative covenants, including, but not limited to the following financial covenants: (i) the ratio of net funded debt to EBITDAX (net income, excluding (i) any non-cash revenue or expense associated with swap contracts resulting from ASC 815 and (ii) any cash or noncash revenue or expense attributable to minority investments plus without duplication and, in the case of expenses, to the extent deducted from revenues in determining net income, the sum of (a) the aggregate amount of consolidated interest expense for such period, (b) the aggregate amount of income, franchise, capital or similar tax expense (other than ad valorem taxes) for such period, (c) all amounts attributable to depletion, depreciation, amortization and asset or goodwill impairment or writedown for such period, (d) all other non-cash charges, (e) exploration costs deducted in determining net income under successful efforts accounting, (f) actual cash distributions received from minority investments, (g) to the extent actually reimbursed by insurance, expenses with respect to liability on casualty events or business interruption, and (h) all reasonable transaction expenses related to dispositions and acquisitions of assets, investments and debt and equity offerings (provided that expenses related to any unsuccessful disposition will be limited to $3.0 million in the aggregate) for a twelve-month period may not be greater than 3.50 to 1.00; for the period December 31, 2014 through June 30, 2015 and 3.25 to 1.00 for the twelve-month period ending September 30, 2015 and periods thereafter; and (ii) the ratio of EBITDAX to interest expense for a twelve-month period may not be less than 3.00 to 1.00. The Company was in compliance with all covenants at March 31, 2015.

StockBased_Compensation_Narrat

Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation [Abstract]
Stock-based compensation expense	$3,500,000	$4,300,000
Capitalized stock-based compensation	1,385,000	1,723,000
Unrecognized compensation expense	$18,900,000
Weighted average period	1 year 6 months 18 days

StockBased_Compensation_Summar

Stock-Based Compensation (Summary Of Stock Option Activity) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding at beginning of period, Shares	5,000
Granted, Shares	0
Exercised, Shares	0
Forfeited/expired, Shares	0
Options Outstanding end of period, Shares	5,000	5,000
Options exercisable at end of period, Shares	5,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Options outstanding at beginning of period, Weighted Average Exercise Price per Share (usd per share)	$9.07
Granted, Weighted Average Exercise Price per Share (usd per share)	$0
Exercised, Weighted Average Exercise Price per Share (usd per share)	$0
Forfeited/expired, Weighted Average Exercise Price per Share (usd per share)	$0
Options outstanding end of period, Weighted Average Exercise Price per Share (usd per share)	$9.07	$9.07
Options exercisable at end of period, Weighted Average Exercise Price per Share (usd per share)	$9.07
Options outstanding, Weighted Average Remaining Contractual Term at beginning of period	0 years 5 months 8 days	0 years 8 months 8 days
Options outstanding, Weighted Average Remaining Contractual Term at end of period	0 years 5 months 8 days	0 years 8 months 8 days
Options exercisable at end of period, Weighted Average Remaining Contractual Term	0 years 5 months 8 days
Options outstanding, Aggregate Intrinsic Value at beginning of period	$163
Options outstanding, Aggregate Intrinsic Value at end of period	184	163
Options exercisable at end of period, Aggregate Intrinsic Value	$184

StockBased_Compensation_Summar1

Stock-Based Compensation (Summary Of Stock Option Plans By Exercise Price) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding (shares)	5,000
Number Exercisable (shares)	5,000
Exercise Price $9.07 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price (usd per share)	$9.07
Number Outstanding (shares)	5,000
Weighted Average Remaining Life (in years)	0 years 5 months 8 days
Number Exercisable (shares)	5,000

StockBased_Compensation_Summar2

Stock-Based Compensation (Summary Of Restricted Stock Award And Unit Activity) (Details) (Restricted Stock [Member], USD $)	3 Months Ended
	Mar. 31, 2015
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Unvested Restricted Shares, beginning of period (shares)	387,245
Granted, Number of Unvested Restricted Shares (shares)	100,226
Vested, Number of Unvested Restricted Shares (shares)	-60,381
Forfeited, Number of Unvested Restricted Shares (shares)	0
Number of Unvested Restricted Shares, end of period (shares)	427,090
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Unvested Restricted Shares, Weighted Average Grant Date Fair Value, beginning of period (usd per share)	$55.87
Granted, Weighted Average Grant Date Fair Value (usd per share)	$44.04
Vested, Weighted Average Grant Date Fair Value (usd per share)	$52.94
Forfeited, Weighted Average Grant Date Fair Value (usd per share)	$0
Unvested Restricted stock, Weighted Average Grant Date Fair Value, end of period (usd per share)	$53.51

Earnings_Per_Share_Schedule_Of

Earnings Per Share (Schedule Of Earnings Per Share Reconciliation) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Basic, Net income	$25,519	$82,558
Effect of dilutive securities, Stock options and awards	0	0
Diluted, Net income	$25,519	$82,558
Weighted average common shares outstanding - Basic (shares)	85,679,606	85,259,407
Effect of dilutive securities, Stock options and awards (shares)	440,424	479,219
Weighted average common shares outstanding-Diluted (shares)	86,120,030	85,738,626
Basic net income from continuing operations per share (usd per share)	$0.30	$0.97
Diluted net income from continuing operations per share (usd per share)	$0.30	$0.96

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	0 Months Ended
In Thousands, unless otherwise specified	Nov. 01, 2012	Mar. 13, 2015	Mar. 11, 1997	Mar. 31, 2015	Dec. 31, 2014
			well
Commitments [Line Items]
Plugging And Abandonment Escrow Account				$3,089	$3,097
Employment Agreement, Term	3 years
Employment Agreement, Subsequent Extension	1 year
Employment Agreement, Notice Period Allowed For Termination	90 days
Other Commitment				183,540
Chief Executive Officer [Member]
Commitments [Line Items]
Other Commitment				400
Chief Operating Officer [Member]
Commitments [Line Items]
Employment Agreement, Term		2 years
Chief Financial Officer [Member]
Commitments [Line Items]
Employment Agreement, Term		3 years
Management [Member]
Commitments [Line Items]
Other Commitment				2,000
WCBB [Member]
Commitments [Line Items]
Purchasing Remaining Percent Interest In Oil And Gas Property			50.00%
Payments Held For Restricted Cash			$18
Significant Plugging Commitment Minimum Number Of Wells To Be Plugged			20
Tenure Of Minimum Wells To Be Plugged			20 years
Number Of Wells Plugged				463

Commitments_and_Contingencies_2

Commitments and Contingencies (Future Minimum Lease Commitments) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
Remaining 2015	$450
2016	524
2017	451
2018	20
2019	0
Total	$1,445

Commitments_and_Contingencies_3

Commitments and Contingencies (Other Commitment Payments) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
Remaining 2015	$39,330
2016	52,440
2017	52,440
2018	39,330
Total other commitment	$183,540

Hedging_Activities_Narrative_D

Hedging Activities (Narrative) (Details) (USD $)	3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	financial_institution		financial_institution
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Number of financial institutions	4		4
Gain on fair value hedge ineffectiveness, net	$31.30	($8.70)

Hedging_Activities_Schedule_Of

Hedging Activities (Schedule Of Derivative Instruments) (Details)	Mar. 31, 2015
Fixed Price Swap, April 2015 through June 2016 [Member]
Derivative [Line Items]
Daily Volume	1,000
Weighted Average Price	62.25
Fixed Price Swap, April 2015 [Member]
Derivative [Line Items]
Daily Volume	191,250
Weighted Average Price	4.05
Fixed Price Swap, May through June 2015 [Member]
Derivative [Line Items]
Daily Volume	201,250
Weighted Average Price	4.05
Fixed Price Swap, July through August 2015 [Member]
Derivative [Line Items]
Daily Volume	216,875
Weighted Average Price	4.04
Fixed Price Swap, September 2015 [Member]
Derivative [Line Items]
Daily Volume	246,875
Weighted Average Price	3.97
Fixed Price Swap, October through December 2015 [Member]
Derivative [Line Items]
Daily Volume	262,500
Weighted Average Price	3.96
Fixed Price Swap, January through March 2016 [Member]
Derivative [Line Items]
Daily Volume	252,500
Weighted Average Price	3.82
Fixed Price Swap, April 2016 [Member]
Derivative [Line Items]
Daily Volume	242,500
Weighted Average Price	3.81
Fixed Price Swap, May through December 2016 [Member]
Derivative [Line Items]
Daily Volume	172,500
Weighted Average Price	3.73
Fixed Price Swap, January through June 2017 [Member]
Derivative [Line Items]
Daily Volume	142,500
Weighted Average Price	3.67
Fixed Price Swap, July through December 2017 [Member]
Derivative [Line Items]
Daily Volume	80,000
Weighted Average Price	3.45
Fixed Price Swap, January through December 2018 [Member]
Derivative [Line Items]
Daily Volume	30,000
Weighted Average Price	3.4
Fixed Price Swap, April 2015 through December 2016, Option One [Member]
Derivative [Line Items]
Daily Volume	30,000
Weighted Average Price	0.02
Fixed Price Swap, April 2015 through December 2016, Option Two [Member]
Derivative [Line Items]
Daily Volume	10,000
Weighted Average Price	0.01

Hedging_Activities_Schedule_Of1

Hedging Activities (Schedule Of Derivative Instruments In Statement Of Financial Position) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Short-term derivative instruments - asset	$93,030	$78,391
Long-term derivative instruments - asset	41,956	24,448
Short-term derivative instruments - liability	$823

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset retirement obligation capitalized	$1,584,000	$1,869,000
Mammoth Energy Partners LP [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity investment			143,500,000
Level 1 [Member] | Fixed Price Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed price swaps	134,986,000
Fixed price swaps	823,000
Level 2 [Member] | Fixed Price Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed price swaps	0
Fixed price swaps	0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset retirement obligation capitalized	1,600,000
Level 3 [Member] | Mammoth Energy Partners LP [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity investment			143,500,000
Level 3 [Member] | Fixed Price Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed price swaps	0
Fixed price swaps	$0

Recovered_Sheet1

Fair Value of Financial Instruments (Details) (USD $)	Mar. 31, 2015	Aug. 18, 2014	Dec. 21, 2012	Oct. 17, 2012
In Millions, unless otherwise specified
Debt Instrument [Line Items]
Fair value of notes	$615.80
October Notes [Member]
Debt Instrument [Line Items]
Unamortized discount	2.8
December Notes [Member]
Debt Instrument [Line Items]
Unamortized premium	0.4
August Notes [Member]
Debt Instrument [Line Items]
Unamortized premium	16.5
Senior Notes [Member]
Debt Instrument [Line Items]
Carrying value of debt	614.1
Unamortized discount				3.7
Unamortized premium		$18	$0.50

Condensed_Consolidating_Financ2

Condensed Consolidating Financial Information - (Details) (Senior Notes [Member], USD $)	Mar. 31, 2015		Dec. 31, 2014		Aug. 18, 2014	Dec. 21, 2012	Oct. 17, 2012
Senior Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Long-term debt	$600,000,000	[1]	$600,000,000	[1]	$600,000,000	$600,000,000	$600,000,000
Stated interest rate					7.75%	7.75%	7.75%
[1]	On October 17, 2012, the Company issued $250.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "October Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act (the "October Notes Offering") under an indenture among the Company, its subsidiary guarantors and Wells Fargo Bank, National Association, as the trustee (the "senior note indenture"). On December 21, 2012, the Company issued an additional $50.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "December Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the December Notes Offering"). The December Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the October Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of the October Notes Offering and the net proceeds of the December Notes Offering for general corporate purposes, which included funding a portion of its 2013 capital development plan. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act in October 2013 (the "Exchange Notes").On August 18, 2014, the Company issued an additional $300.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "August Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the August Notes Offering"). The August Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the August Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company intends to use the remaining net proceeds of the August Notes Offering for general corporate purposes, including funding a portion of its 2014 and 2015 capital development plans. The October Notes Offering, December Notes Offering and the August Notes Offering are collectively referred to as the "Notes Offerings" and the Exchange Notes, and the August Notes are collectively referred to as the "Old Notes".In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Notes was completed in March 2015.Under the senior note indenture relating to the Old Notes, interest on the Old Notes accrues at a rate of 7.75% per annum on the outstanding principal amount from October 17, 2012, payable semi-annually on May 1 and November 1 of each year, commencing on May 1, 2013. The Old Notes are the Company's senior unsecured obligations and rank equally in the right of payment with all of the Company's other senior indebtedness and senior in right of payment to any future subordinated indebtedness. All of the Company's existing and future restricted subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt guarantee the Old Notes; provided, however, that the Old Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company's future unrestricted subsidiaries. The Company may redeem some or all of the Old Notes at any time on or after November 1, 2016, at the redemption prices listed in the senior note indenture. Prior to November 1, 2016, the Company may redeem the Old Notes at a price equal to 100% of the principal amount plus a “make-whole” premium. In addition, prior to November 1, 2015, the Company may redeem up to 35% of the aggregate principal amount of the Old Notes with the net proceeds of certain equity offerings, provided that at least 65% of the aggregate principal amount of the Old Notes initially issued remains outstanding immediately after such redemption.

Condensed_Consolidating_Financ3

Condensed Consolidating Financial Information - Condensed Consolidating Balance Sheets (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$74,740	$142,340	$170,382	$458,956
Accounts receivable—oil and gas	79,680	103,858
Accounts receivable - related parties	33	46
Accounts receivable - intercompany		0
Prepaid expenses and other current assets	15,777	3,714
Short-term derivative instruments	93,030	78,391
Total current assets	263,260	328,349
Property and equipment:
Oil and natural gas properties	4,177,962	3,923,154
Other property and equipment	19,051	18,344
Accumulated depletion, depreciation, amortization and impairment	-1,140,168	-1,050,879
Property and equipment, net	3,056,845	2,890,619
Other assets:
Equity investments and investments in subsidiaries	374,971	369,581
Derivative instruments	41,956	24,448
Other assets	18,566	19,396
Total other assets	435,493	413,425
Total assets	3,755,598	3,632,393
Current liabilities:
Accounts payable and accrued liabilities	400,096	371,410
Accounts payable - intercompany	0	0
Asset retirement obligation—current	75	75	795
Short-term derivative instruments	823
Deferred tax liability - current	29,622	27,070
Current maturities of long-term debt	1,781	168
Total current liabilities	432,397	398,723
Long-term derivative instrument	0
Asset retirement obligation—long-term	18,656	17,863	14,650
Deferred tax liability	215,122	203,195
Long-term debt, net of current maturities	779,130	716,316
Total liabilities	1,445,305	1,336,097
Stockholders’ equity:
Common stock	857	856
Paid-in capital	1,832,063	1,828,602
Accumulated other comprehensive income (loss)	-41,659	-26,675
Retained earnings (accumulated deficit)	519,032	493,513
Total stockholders’ equity	2,310,293	2,296,296	2,130,440	2,050,238
Total liabilities and stockholders’ equity	3,755,598	3,632,393
Parent [Member]
Current assets:
Cash and cash equivalents	73,667	141,535	168,476	451,431
Accounts receivable—oil and gas	79,621	103,762
Accounts receivable - related parties	33	46
Accounts receivable - intercompany	48,154	45,222
Prepaid expenses and other current assets	15,777	3,714
Short-term derivative instruments	93,030	78,391
Total current assets	310,282	372,670
Property and equipment:
Oil and natural gas properties	4,139,903	3,887,874
Other property and equipment	19,008	18,301
Accumulated depletion, depreciation, amortization and impairment	-1,140,142	-1,050,855
Property and equipment, net	3,018,769	2,855,320
Other assets:
Equity investments and investments in subsidiaries	365,840	360,238
Derivative instruments	41,956	24,448
Other assets	18,566	19,396
Total other assets	426,362	404,082
Total assets	3,755,413	3,632,072
Current liabilities:
Accounts payable and accrued liabilities	399,912	371,089
Accounts payable - intercompany	0	0
Asset retirement obligation—current	75	75
Short-term derivative instruments	823
Deferred tax liability - current	29,622	27,070
Current maturities of long-term debt	1,781	168
Total current liabilities	432,213	398,402
Long-term derivative instrument	0
Asset retirement obligation—long-term	18,656	17,863
Deferred tax liability	215,122	203,195
Long-term debt, net of current maturities	779,130	716,316
Total liabilities	1,445,121	1,335,776
Stockholders’ equity:
Common stock	857	856
Paid-in capital	1,832,062	1,828,602
Accumulated other comprehensive income (loss)	-41,659	-26,675
Retained earnings (accumulated deficit)	519,032	493,513
Total stockholders’ equity	2,310,292	2,296,296
Total liabilities and stockholders’ equity	3,755,413	3,632,072
Guarantors [Member]
Current assets:
Cash and cash equivalents	1,072	804	1,906	7,525
Accounts receivable—oil and gas	59	96
Accounts receivable - related parties	0	0
Accounts receivable - intercompany	26	27
Prepaid expenses and other current assets		0
Short-term derivative instruments	0	0
Total current assets	1,157	927
Property and equipment:
Oil and natural gas properties	38,769	35,990
Other property and equipment	43	43
Accumulated depletion, depreciation, amortization and impairment	-26	-24
Property and equipment, net	38,786	36,009
Other assets:
Equity investments and investments in subsidiaries		0
Derivative instruments	0	0
Other assets		0
Total assets	39,943	36,936
Current liabilities:
Accounts payable and accrued liabilities	184	321
Accounts payable - intercompany	48,072	45,143
Asset retirement obligation—current		0
Deferred tax liability - current		0
Current maturities of long-term debt		0
Total current liabilities	48,256	45,464
Long-term derivative instrument	0
Asset retirement obligation—long-term	0	0
Deferred tax liability		0
Long-term debt, net of current maturities	0	0
Total liabilities	48,256	45,464
Stockholders’ equity:
Common stock		0
Paid-in capital	321	322
Accumulated other comprehensive income (loss)		0
Retained earnings (accumulated deficit)	-8,634	-8,850
Total stockholders’ equity	-8,313	-8,528
Total liabilities and stockholders’ equity	39,943	36,936
Non-Guarantor [Member]
Current assets:
Cash and cash equivalents	1	1	0	0
Accounts receivable—oil and gas	0	0
Accounts receivable - related parties	0	0
Accounts receivable - intercompany	0	0
Prepaid expenses and other current assets	0	0
Short-term derivative instruments	0	0
Total current assets	1	1
Property and equipment:
Oil and natural gas properties		0
Other property and equipment		0
Accumulated depletion, depreciation, amortization and impairment		0
Property and equipment, net		0
Other assets:
Equity investments and investments in subsidiaries	167,186	180,217
Derivative instruments	0	0
Other assets		0
Total other assets	167,186	180,217
Total assets	167,187	180,218
Current liabilities:
Accounts payable and accrued liabilities		0
Accounts payable - intercompany	108	106
Asset retirement obligation—current		0
Deferred tax liability - current		0
Current maturities of long-term debt		0
Total current liabilities	108	106
Long-term derivative instrument	0
Asset retirement obligation—long-term	0	0
Deferred tax liability		0
Long-term debt, net of current maturities	0	0
Total liabilities	108	106
Stockholders’ equity:
Common stock		0
Paid-in capital	233,174	227,079
Accumulated other comprehensive income (loss)	-41,659	-26,675
Retained earnings (accumulated deficit)	-24,436	-20,292
Total stockholders’ equity	167,079	180,112
Total liabilities and stockholders’ equity	167,187	180,218
Eliminations [Member]
Current assets:
Cash and cash equivalents	0	0	0	0
Accounts receivable—oil and gas		0
Accounts receivable - related parties	0	0
Accounts receivable - intercompany	-48,180	-45,249
Prepaid expenses and other current assets		0
Short-term derivative instruments	0	0
Total current assets	-48,180	-45,249
Property and equipment:
Oil and natural gas properties	-710	-710
Other property and equipment		0
Accumulated depletion, depreciation, amortization and impairment		0
Property and equipment, net	-710	-710
Other assets:
Equity investments and investments in subsidiaries	-158,055	-170,874
Derivative instruments	0	0
Other assets		0
Total other assets	-158,055	-170,874
Total assets	-206,945	-216,833
Current liabilities:
Accounts payable and accrued liabilities		0
Accounts payable - intercompany	-48,180	-45,249
Asset retirement obligation—current		0
Deferred tax liability - current		0
Current maturities of long-term debt		0
Total current liabilities	-48,180	-45,249
Long-term derivative instrument	0
Asset retirement obligation—long-term	0	0
Deferred tax liability		0
Long-term debt, net of current maturities	0	0
Total liabilities	-48,180	-45,249
Stockholders’ equity:
Common stock		0
Paid-in capital	-233,494	-227,401
Accumulated other comprehensive income (loss)	41,659	26,675
Retained earnings (accumulated deficit)	33,070	29,142
Total stockholders’ equity	-158,765	-171,584
Total liabilities and stockholders’ equity	($206,945)	($216,833)

Condensed_Consolidating_Financ4

Condensed Consolidating Financial Information - Condensed Consolidating Statement of Operations (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues:
Total revenues	$176,317	$118,029
Costs and expenses:
Lease operating expenses	16,980	11,629
Production taxes	4,285	6,957
Midstream gathering and processing	25,381	7,769
Depreciation, depletion and amortization	89,909	56,877
General and administrative	10,799	9,511
Accretion expense	190	188
Gain on sale of assets	0	-11
Total costs and expenses	147,544	92,920
INCOME FROM OPERATIONS	28,773	25,109
OTHER (INCOME) EXPENSE:
Interest expense	8,759	3,885
Interest income	-9	-106
Litigation settlement	0	18,000
Income from equity method investments	-19,975	-128,475
Total Other (Income) Expense	-11,225	-106,696
INCOME BEFORE INCOME TAXES	39,998	131,805
INCOME TAX EXPENSE	14,479	49,247
NET INCOME	25,519	82,558
Parent [Member]
Revenues:
Total revenues	175,832	117,850
Costs and expenses:
Lease operating expenses	16,787	11,381
Production taxes	4,253	6,937
Midstream gathering and processing	25,374	7,757
Depreciation, depletion and amortization	89,908	56,877
General and administrative	10,761	9,488
Accretion expense	190	188
Gain on sale of assets		-11
Total costs and expenses	147,273	92,617
INCOME FROM OPERATIONS	28,559	25,233
OTHER (INCOME) EXPENSE:
Interest expense	8,759	3,885
Interest income	-9	-106
Litigation settlement		18,000
Income from equity method investments	-20,189	-128,351
Total Other (Income) Expense	-11,439	-106,572
INCOME BEFORE INCOME TAXES	39,998	131,805
INCOME TAX EXPENSE	14,479	49,247
NET INCOME	25,519	82,558
Guarantors [Member]
Revenues:
Total revenues	485	179
Costs and expenses:
Lease operating expenses	193	248
Production taxes	32	20
Midstream gathering and processing	7	12
Depreciation, depletion and amortization	1	0
General and administrative	36	27
Accretion expense	0	0
Gain on sale of assets		0
Total costs and expenses	269	307
INCOME FROM OPERATIONS	216	-128
OTHER (INCOME) EXPENSE:
Interest expense	0	0
Interest income	0	0
Litigation settlement		0
Income from equity method investments	0	0
Total Other (Income) Expense	0	0
INCOME BEFORE INCOME TAXES	216	-128
INCOME TAX EXPENSE	0	0
NET INCOME	216	-128
Non-Guarantor [Member]
Revenues:
Total revenues	0	0
Costs and expenses:
Lease operating expenses	0	0
Production taxes	0	0
Midstream gathering and processing	0	0
Depreciation, depletion and amortization	0	0
General and administrative	2	-4
Accretion expense	0	0
Gain on sale of assets		0
Total costs and expenses	2	-4
INCOME FROM OPERATIONS	-2	4
OTHER (INCOME) EXPENSE:
Interest expense	0	0
Interest income	0	0
Litigation settlement		0
Income from equity method investments	4,142	2,001
Total Other (Income) Expense	4,142	2,001
INCOME BEFORE INCOME TAXES	-4,144	-1,997
INCOME TAX EXPENSE	0	0
NET INCOME	-4,144	-1,997
Eliminations [Member]
Revenues:
Total revenues	0	0
Costs and expenses:
Lease operating expenses	0	0
Production taxes	0	0
Midstream gathering and processing	0	0
Depreciation, depletion and amortization	0	0
General and administrative	0	0
Accretion expense	0	0
Gain on sale of assets		0
Total costs and expenses	0	0
INCOME FROM OPERATIONS	0	0
OTHER (INCOME) EXPENSE:
Interest expense	0	0
Interest income	0	0
Litigation settlement		0
Income from equity method investments	-3,928	-2,125
Total Other (Income) Expense	-3,928	-2,125
INCOME BEFORE INCOME TAXES	3,928	2,125
INCOME TAX EXPENSE	0	0
NET INCOME	$3,928	$2,125

Condensed_Consolidating_Financ5

Condensed Consolidating Financial Information - Condensed Consolidating Statements of Comprehensive Income (Loss) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Net income	$25,519	$82,558
Foreign currency translation adjustment	-14,984	-7,278
Other comprehensive loss	-14,984	-7,278
Comprehensive income	10,535	75,280
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	25,519	82,558
Foreign currency translation adjustment	-14,984	-7,278
Other comprehensive loss	-14,984	-7,278
Comprehensive income	10,535	75,280
Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	216	-128
Foreign currency translation adjustment	0	0
Other comprehensive loss	0	0
Comprehensive income	216	-128
Non-Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	-4,144	-1,997
Foreign currency translation adjustment	-14,984	-7,278
Other comprehensive loss	-14,984	-7,278
Comprehensive income	-19,128	-9,275
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	3,928	2,125
Foreign currency translation adjustment	14,984	7,278
Other comprehensive loss	14,984	7,278
Comprehensive income	$18,912	$9,403

Condensed_Consolidating_Financ6

Condensed Consolidating Financial Information - Condensed Consolidating Statement of Cash Flows (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	$99,037	$156,150
Net cash provided by (used in) investing activities	-231,491	-445,112
Net cash provided by (used in) financing activities	64,854	388
Net decrease in cash and cash equivalents	-67,600	-288,574
Cash and cash equivalents at beginning of period	142,340	458,956
Cash and cash equivalents at end of period	74,740	170,382
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	95,879	159,736
Net cash provided by (used in) investing activities	-228,601	-443,079
Net cash provided by (used in) financing activities	64,854	388
Net decrease in cash and cash equivalents	-67,868	-282,955
Cash and cash equivalents at beginning of period	141,535	451,431
Cash and cash equivalents at end of period	73,667	168,476
Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	3,158	-3,585
Net cash provided by (used in) investing activities	-2,890	-2,034
Net cash provided by (used in) financing activities	0	0
Net decrease in cash and cash equivalents	268	-5,619
Cash and cash equivalents at beginning of period	804	7,525
Cash and cash equivalents at end of period	1,072	1,906
Non-Guarantor [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	0	-1
Net cash provided by (used in) investing activities	-6,093	-8,069
Net cash provided by (used in) financing activities	6,093	8,070
Net decrease in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	1	0
Cash and cash equivalents at end of period	1	0
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	0	0
Net cash provided by (used in) investing activities	6,093	8,070
Net cash provided by (used in) financing activities	-6,093	-8,070
Net decrease in cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$0	$0

Subsequent_Events_Details

Subsequent Events (Details) (USD $)	3 Months Ended		0 Months Ended
	Mar. 31, 2014	Sep. 30, 2015	Apr. 21, 2015	Apr. 29, 2015	Apr. 16, 2015	Mar. 31, 2015	Aug. 18, 2014	Dec. 21, 2012	Oct. 17, 2012	Apr. 30, 2015	Apr. 15, 2015
											acre
Subsequent Event [Line Items]
Proceeds from issuance of common stock, net of offering costs and exercise of stock options	$615,000
Fixed Price Swap, October through December 2015 [Member]
Subsequent Event [Line Items]
Daily Volume (in MMBtu per day)						262,500
Weighted Average Price (in usd per MMBtu)						3.96
Senior Notes [Member]
Subsequent Event [Line Items]
Stated interest rate							7.75%	7.75%	7.75%
Scenario, Forecast [Member] | Paloma Partners III, LLC [Member]
Subsequent Event [Line Items]
Purchase price		301,300,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from issuance of common stock, net of offering costs and exercise of stock options			501,900,000
Subsequent Event [Member] | Fixed Price Swap, June 2015 through June 2016 [Member]
Subsequent Event [Line Items]
Daily Volume (in MMBtu per day)										1,500
Weighted Average Price (in usd per MMBtu)										62.47
Subsequent Event [Member] | Fixed Price Swap, October through December 2015 [Member]
Subsequent Event [Line Items]
Daily Volume (in MMBtu per day)										20,000
Weighted Average Price (in usd per MMBtu)										3.26
Subsequent Event [Member] | Fixed Price Swap, January 2016 through December 2016 [Member]
Subsequent Event [Line Items]
Daily Volume (in MMBtu per day)										40,000
Weighted Average Price (in usd per MMBtu)										3.32
Subsequent Event [Member] | Fixed Price Swap, January 2017 through December 2018 [Member]
Subsequent Event [Line Items]
Daily Volume (in MMBtu per day)										20,000
Weighted Average Price (in usd per MMBtu)										3.26
Subsequent Event [Member] | Swaption Contract, January 2016 through December 2016 [Member] [Member]
Subsequent Event [Line Items]
Daily Volume (in MMBtu per day)										20,000
Weighted Average Price (in usd per MMBtu)										3.38
Subsequent Event [Member] | Chief Executive Officer [Member]
Subsequent Event [Line Items]
Employment agreement, annual salary				460,000
Subsequent Event [Member] | Restricted Stock [Member] | Chief Executive Officer [Member]
Subsequent Event [Line Items]
Employment agreement, annual grant (in shares)				40,000
Employment agreement, percent of salary awarded in shares				500.00%
Subsequent Event [Member] | Senior Notes [Member] | Notes Due 2023 [Member]
Subsequent Event [Line Items]
Debt instrument, amount					350,000,000
Stated interest rate					6.63%
Proceeds from debt, net of issuance costs					$343,600,000
Subsequent Event [Member] | Common Stock [Member]
Subsequent Event [Line Items]
Stock issued in underwritten public offering (in shares)			10,925,000
Subsequent Event [Member] | Common Stock [Member] | Over-Allotment Option [Member]
Subsequent Event [Line Items]
Stock issued in underwritten public offering (in shares)			1,425,000
Subsequent Event [Member] | Paloma Partners III, LLC [Member]
Subsequent Event [Line Items]
Gas and oil acreage, undeveloped, net											24,000