Gulfport Energy (GPOR) 10-Q 2 Aug 19 2019 Q2 Quarterly report Financial data

COVER PAGE

COVER PAGE - shares	6 Months Ended
	Jun. 30, 2019	Jul. 26, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	000-19514
Entity Registrant Name	Gulfport Energy Corp
Entity Central Index Key	0000874499
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	73-1521290
Entity Address, Address Line One	3001 Quail Springs Parkway
Entity Address, City or Town	Oklahoma City,
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	73134
City Area Code	405
Local Phone Number	252-4600
Title of 12(b) Security	Common stock, par value $0.01 per share
Trading Symbol	GPOR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		159,396,017

CONSOLIDATED BALANCE SHEETS (UN

CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 20,777	$ 52,297
Accounts receivable—oil and natural gas sales	131,675	210,200
Accounts receivable—joint interest and other	46,645	22,497
Prepaid expenses and other current assets	9,474	10,607
Short-term derivative instruments	134,920	21,352
Total current assets	343,491	316,953
Property and equipment:
Oil and natural gas properties, full-cost accounting, $2,836,441 and $2,873,037 excluded from amortization in 2019 and 2018, respectively	10,510,427	10,026,836
Other property and equipment	96,413	92,667
Accumulated depletion, depreciation, amortization and impairment	(4,882,729)	(4,640,098)
Property and equipment, net	5,724,111	5,479,405
Other assets:
Equity investments	119,307	236,121
Long-term derivative instruments	5,036	0
Deferred tax asset	179,331	0
Inventories	9,001	4,754
Operating lease assets	19,334
Operating lease assets - related parties	53,579
Other assets	12,280	13,803
Total other assets	397,868	254,678
Total assets	6,465,470	6,051,036
Current liabilities:
Accounts payable and accrued liabilities	493,830	518,380
Short-term derivative instruments	198	20,401
Current portion of operating lease liabilities	17,999
Current portion of operating lease liabilities - related parties	20,817
Current maturities of long-term debt	615	651
Total current liabilities	533,459	539,432
Long-term derivative instruments	210	13,992
Asset retirement obligation—long-term	88,491	79,952
Deferred tax liability	3,127	3,127
Non-current operating lease liabilities	1,335
Non-current operating lease liabilities - related parties	32,762
Long-term debt, net of current maturities	2,198,678	2,086,765
Total liabilities	2,858,062	2,723,268
Commitments and contingencies (Note 7)
Preferred stock, $0.01 par value; 5,000,000 shares authorized (30,000 authorized as redeemable 12% cumulative preferred stock, Series A), and none issued and outstanding	0	0
Stockholders’ equity:
Common stock - $0.01 par value, 200,000,000 shares authorized, 159,396,017 issued and outstanding at June 30, 2019 and 162,986,045 at December 31, 2018	1,594	1,630
Paid-in capital	4,202,599	4,227,532
Accumulated other comprehensive loss	(48,615)	(56,026)
Accumulated deficit	(548,170)	(845,368)
Total stockholders’ equity	3,607,408	3,327,768
Total liabilities and stockholders’ equity	$ 6,465,470	$ 6,051,036

CONSOLIDATED BALANCE SHEETS (_2

CONSOLIDATED BALANCE SHEETS (UNAUDITED) (PARENTHETICAL) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Capitalized costs of oil and natural gas properties excluded from amortization	$ 2,836,441	$ 2,873,037
Preferred stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, dividend rate	12.00%	12.00%
Preferred stock, shares authorized (in shares)	30,000	30,000
Preferred stock Series A, issued (in shares)	0	0
Preferred stock Series A, outstanding (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares, issued (in shares)	159,396,017	162,986,045
Common stock, shares, outstanding (in shares)	159,396,017	162,986,045

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues:
Net gain (loss) on natural gas, oil, and NGLs derivatives	$ 171,140	$ (70,545)	$ 151,095	$ (87,074)
Total revenues	458,994	252,740	779,572	578,132
Costs and expenses:
Lease operating expenses	22,388	22,912	42,195	41,818
Production taxes	8,098	7,659	16,019	14,513
Midstream gathering and processing expenses	72,015	71,440	142,297	135,633
Depreciation, depletion and amortization	124,951	121,915	243,384	232,933
General and administrative expenses	13,265	14,008	24,823	27,107
Accretion expense	1,359	1,015	2,426	2,019
Total costs and expenses	242,076	238,949	471,144	454,023
INCOME (LOSS) FROM OPERATIONS	216,918	13,791	308,428	124,109
OTHER EXPENSE (INCOME):
Interest expense	34,880	33,704	69,000	67,669
Interest income	(159)	(33)	(311)	(70)
Insurance proceeds	83	231	83	231
Gain on sale of equity investments and other assets	0	(122,035)	0	(122,035)
Loss (income) from equity method investments, net	125,582	(8,888)	121,309	(22,424)
Other expense (income)	1,073	(45)	646	(140)
Total other (income) expense	161,293	(97,528)	190,561	(77,231)
INCOME (LOSS) BEFORE INCOME TAXES	55,625	111,319	117,867	201,340
INCOME TAX BENEFIT	(179,331)	0	(179,331)	(69)
NET INCOME (LOSS)	$ 234,956	$ 111,319	$ 297,198	$ 201,409
NET INCOME PER COMMON SHARE:
Basic (in usd per share)	$ 1.47	$ 0.64	$ 1.85	$ 1.14
Diluted (in usd per share)	$ 1.47	$ 0.64	$ 1.84	$ 1.13
Weighted average common shares outstanding - Basic (in shares)	159,324,909	173,623,630	161,064,787	177,158,230
Weighted average common shares outstanding - Diluted (in shares)	159,506,826	174,140,627	161,590,087	177,737,282
Natural gas sales
Revenues:
Revenue from contract with customer	$ 225,257	$ 232,695	$ 501,273	$ 482,094
Oil and condensate sales
Revenues:
Revenue from contract with customer	36,910	49,319	69,392	95,005
Natural gas liquid sales
Revenues:
Revenue from contract with customer	$ 25,687	$ 41,271	$ 57,812	$ 88,107

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 234,956	$ 62,242	$ 111,319	$ 90,090	$ 297,198	$ 201,409
Foreign currency translation adjustment	3,610		(3,364)		7,411	(8,867)
Other comprehensive income (loss)	3,610	$ 3,801	(3,364)	$ (5,503)	7,411	(8,867)
Comprehensive income	$ 238,566		$ 107,955		$ 304,609	$ 192,542

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Common Stock	Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2017		183,105,910
Beginning balance at Dec. 31, 2017	$ 3,101,614	$ 1,831	$ 4,416,250	$ (40,539)	$ (1,275,928)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	90,090				90,090
Other Comprehensive Income (Loss)	(5,503)			(5,503)
Stock Compensation	2,685		2,685
Shares Repurchased (in shares)		(9,692,356)
Shares Repurchased	(99,997)	$ (97)	(99,900)
Issuance of Restricted Stock (in shares)		109,933
Issuance of Restricted Stock	0	$ 1	(1)
Ending balance (in shares) at Mar. 31, 2018		173,523,487
Ending balance at Mar. 31, 2018	3,088,889	$ 1,735	4,319,034	(46,042)	(1,185,838)
Beginning balance (in shares) at Dec. 31, 2017		183,105,910
Beginning balance at Dec. 31, 2017	3,101,614	$ 1,831	4,416,250	(40,539)	(1,275,928)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	201,409
Other Comprehensive Income (Loss)	(8,867)
Ending balance (in shares) at Jun. 30, 2018		173,302,055
Ending balance at Jun. 30, 2018	3,195,199	$ 1,733	4,317,391	(49,406)	(1,074,519)
Beginning balance (in shares) at Dec. 31, 2017		183,105,910
Beginning balance at Dec. 31, 2017	$ 3,101,614	$ 1,831	4,416,250	(40,539)	(1,275,928)
Ending balance (in shares) at Dec. 31, 2018	162,986,045	162,986,045
Ending balance at Dec. 31, 2018	$ 3,327,768	$ 1,630	4,227,532	(56,026)	(845,368)
Beginning balance (in shares) at Mar. 31, 2018		173,523,487
Beginning balance at Mar. 31, 2018	3,088,889	$ 1,735	4,319,034	(46,042)	(1,185,838)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	111,319				111,319
Other Comprehensive Income (Loss)	(3,364)			(3,364)
Stock Compensation	3,355		3,355
Shares Repurchased (in shares)		(412,516)
Shares Repurchased	(5,000)	$ (4)	(4,996)
Issuance of Restricted Stock (in shares)		191,084
Issuance of Restricted Stock	0	$ 2	(2)
Ending balance (in shares) at Jun. 30, 2018		173,302,055
Ending balance at Jun. 30, 2018	$ 3,195,199	$ 1,733	4,317,391	(49,406)	(1,074,519)
Beginning balance (in shares) at Dec. 31, 2018	162,986,045	162,986,045
Beginning balance at Dec. 31, 2018	$ 3,327,768	$ 1,630	4,227,532	(56,026)	(845,368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	62,242				62,242
Other Comprehensive Income (Loss)	3,801			3,801
Stock Compensation	2,785		2,785
Shares Repurchased (in shares)		(3,618,634)
Shares Repurchased	(28,330)	$ (37)	(28,293)
Issuance of Restricted Stock (in shares)		54,554
Issuance of Restricted Stock	0	$ 1	(1)
Ending balance (in shares) at Mar. 31, 2019		159,421,965
Ending balance at Mar. 31, 2019	$ 3,368,266	$ 1,594	4,202,023	(52,225)	(783,126)
Beginning balance (in shares) at Dec. 31, 2018	162,986,045	162,986,045
Beginning balance at Dec. 31, 2018	$ 3,327,768	$ 1,630	4,227,532	(56,026)	(845,368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	297,198
Other Comprehensive Income (Loss)	$ 7,411
Ending balance (in shares) at Jun. 30, 2019	159,396,017	159,396,017
Ending balance at Jun. 30, 2019	$ 3,607,408	$ 1,594	4,202,599	(48,615)	(548,170)
Beginning balance (in shares) at Mar. 31, 2019		159,421,965
Beginning balance at Mar. 31, 2019	3,368,266	$ 1,594	4,202,023	(52,225)	(783,126)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	234,956				234,956
Other Comprehensive Income (Loss)	3,610			3,610
Stock Compensation	2,846		2,846
Shares Repurchased (in shares)		(296,587)
Shares Repurchased	(2,270)	$ (3)	(2,267)
Issuance of Restricted Stock (in shares)		270,639
Issuance of Restricted Stock	$ 0	$ 3	(3)
Ending balance (in shares) at Jun. 30, 2019	159,396,017	159,396,017
Ending balance at Jun. 30, 2019	$ 3,607,408	$ 1,594	$ 4,202,599	$ (48,615)	$ (548,170)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income	$ 297,198	$ 201,409
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion expense	2,426	2,019
Depletion, depreciation and amortization	243,384	232,933
Stock-based compensation expense	3,379	3,624
Loss (income) from equity investments	121,449	(22,322)
Change in fair value of derivative instruments	(152,589)	102,248
Deferred income tax benefit	(179,331)	(69)
Amortization of loan costs	3,191	3,006
Gain on sale of equity investments and other assets	(112)	(122,035)
Distributions from equity method investments	2,457	0
Changes in operating assets and liabilities:
Decrease in accounts receivable—oil and natural gas sales	78,525	6,564
Increase in accounts receivable—joint interest and other	(24,148)	(16,385)
Increase in accounts receivable—related parties	0	(110)
Decrease (increase) in prepaid expenses and other current assets	1,133	(5,786)
Increase in other assets	(296)	(1,517)
(Decrease) increase in accounts payable, accrued liabilities and other	(87,560)	28,184
Settlement of asset retirement obligation	(117)	(719)
Net cash provided by operating activities	308,989	411,044
Cash flows from investing activities:
Additions to other property and equipment	(4,298)	(6,252)
Additions to oil and natural gas properties	(417,535)	(579,734)
Proceeds from sale of oil and natural gas properties	745	3,762
Proceeds from sale of other property and equipment	130	167
Proceeds from sale of equity method investments	0	221,965
Contributions to equity method investments	(432)	(1,569)
Distributions from equity method investments	1,945	1,196
Net cash used in investing activities	(419,445)	(360,465)
Cash flows from financing activities:
Principal payments on borrowings	(345,350)	(150,285)
Borrowings on line of credit	455,000	225,000
Debt issuance costs and loan commitment fees	(114)	(624)
Payments for repurchase of stock	(30,600)	(104,997)
Net cash provided by (used in) financing activities	78,936	(30,906)
Net (decrease) increase in cash, cash equivalents and restricted cash	(31,520)	19,673
Cash, cash equivalents and restricted cash at beginning of period	52,297	99,557
Cash, cash equivalents and restricted cash at end of period	20,777	119,230
Supplemental disclosure of cash flow information:
Interest payments	67,472	59,915
Income tax receipts	(1,794)	0
Supplemental disclosure of non-cash transactions:
Capitalized stock-based compensation	2,252	2,416
Asset retirement obligation capitalized	6,230	535
Interest capitalized	1,771	2,351
Foreign currency translation gain (loss) on equity method investments	$ 7,411	$ (8,867)

NOTES TO CONSOLIDATED FINANCIAL

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS	These consolidated financial statements have been prepared by Gulfport Energy Corporation (the “Company” or “Gulfport”) without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”), and reflect all adjustments that, in the opinion of management, are necessary for a fair presentation of the results for the interim periods in all material respects, on a basis consistent with the annual audited consolidated financial statements. All such adjustments are of a normal, recurring nature. Certain information, accounting policies, and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles ("GAAP") have been omitted pursuant to such rules and regulations, although the Company believes that the disclosures are adequate to make the information presented not misleading. These consolidated financial statements should be read in conjunction with the consolidated financial statements and the summary of significant accounting policies and notes included in the Company’s most recent annual report on Form 10-K. Results for the three and six months ended June 30, 2019

PROPERTY AND EQUIPMENT

PROPERTY AND EQUIPMENT	6 Months Ended
	Jun. 30, 2019
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 June 30, 2019 and December 31, 2018 are as follows: June 30, 2019 December 31, 2018 (In thousands) Oil and natural gas properties $ 10,510,427 $ 10,026,836 Office furniture and fixtures 46,327 42,581 Building 44,565 44,565 Land 5,521 5,521 Total property and equipment 10,606,840 10,119,503 Accumulated depletion, depreciation, amortization and impairment (4,882,729 ) (4,640,098 ) Property and equipment, net $ 5,724,111 $ 5,479,405 Under the full cost method of accounting, the Company is required to perform a ceiling test each quarter. The test determines a limit, or ceiling, on the book value of the Company's oil and natural gas properties. At June 30, 2019 , the calculated ceiling was greater than the net book value of the Company’s oil and natural gas properties, and no ceiling test impairment was required for the three and six months ended June 30, 2019 . No impairment was required for oil and natural gas properties for the three and six months ended June 30, 2018 . Included in oil and natural gas properties at June 30, 2019 is the cumulative capitalization of $219.8 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 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 $8.8 million and $16.5 million for the three and six months ended June 30, 2019 , respectively, and $9.4 million and $18.2 million for the three and six months ended June 30, 2018 , respectively. The average depletion rate per Mcfe, which is a function of capitalized costs, future development costs and the related underlying reserves in the periods presented, was $1.00 and $0.96 per Mcfe for the six months ended June 30, 2019 and 2018 , respectively. The following table summarizes the Company’s non-producing properties excluded from amortization by area at June 30, 2019 : June 30, 2019 (In thousands) Utica $ 1,475,997 MidContinent 1,359,279 Niobrara 454 Southern Louisiana 611 Bakken 100 $ 2,836,441 At December 31, 2018 , approximately $2.9 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 typically occurs within three to five years . However, the majority of the Company’s non-producing leases in the Utica Shale have five-year extension terms which could extend this time frame beyond five years. A reconciliation of the Company’s asset retirement obligation for the six months ended June 30, 2019 and 2018 is as follows: June 30, 2019 June 30, 2018 (In thousands) Asset retirement obligation, beginning of period $ 79,952 $ 75,100 Liabilities incurred 5,153 909 Liabilities settled (117 ) (719 ) Accretion expense 2,426 2,019 Revisions in estimated cash flows 1,077 (374 ) Asset retirement obligation as of end of period 88,491 76,935 Less current portion — 120 Asset retirement obligation, long-term $ 88,491 $ 76,815

EQUITY INVESTMENTS

EQUITY INVESTMENTS	6 Months Ended
	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
EQUITY INVESTMENTS	EQUITY INVESTMENTS Investments accounted for by the equity method consist of the following as of June 30, 2019 and December 31, 2018 : Carrying value Loss (income) from equity method investments Approximate ownership % June 30, 2019 December 31, 2018 Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (In thousands) Investment in Tatex Thailand II, LLC 23.5 % $ — $ — $ (1,945 ) $ (63 ) $ (2,085 ) $ (104 ) Investment in Grizzly Oil Sands ULC 24.9999 % 51,607 44,259 (54 ) 228 339 558 Investment in Timber Wolf Terminals LLC (1) — % — — — 534 — 536 Investment in Windsor Midstream LLC 22.5 % 39 39 — (9 ) — (9 ) Investment in Mammoth Energy Services, Inc. 21.8 % 67,661 191,823 127,581 (9,242 ) 123,055 (22,712 ) Investment in Strike Force Midstream LLC (2) — % — — — (336 ) — (693 ) $ 119,307 $ 236,121 $ 125,582 $ (8,888 ) $ 121,309 $ (22,424 ) (1) On June 5, 2018, the Company received its final distribution from Timber Wolf Terminals LLC ("Timber Wolf"). See below under Timber Wolf Terminals LLC for information regarding the subsequent dissolution of Timber Wolf. (2) On May 1, 2018, the Company sold its 25% interest in Strike Force Midstream LLC ("Strike Force") to EQT Midstream Partners, LP. See below under Strike Force Midstream LLC for information regarding this transaction. The tables below summarize financial information for the Company’s equity investments as of June 30, 2019 and December 31, 2018 . Summarized balance sheet information: June 30, 2019 December 31, 2018 (In thousands) Current assets $ 477,559 $ 471,733 Noncurrent assets $ 1,353,113 $ 1,302,488 Current liabilities $ 167,901 $ 239,975 Noncurrent liabilities $ 190,200 $ 94,575 Summarized results of operations: Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (In thousands) Gross revenue $ 179,114 $ 566,404 $ 443,958 $ 1,067,537 Net (loss) income $ (4,072 ) $ 49,018 $ 20,684 $ 113,470 Tatex Thailand II, LLC The Company has an indirect ownership interest in Tatex Thailand II, LLC ("Tatex II"). Tatex II held an 8.5% interest in APICO, LLC (“APICO”), an international oil and gas exploration company, before selling its interest in June 2019. APICO has a reserve base located in Southeast Asia through its ownership of concessions covering approximately 108,000 acres which includes the Phu Horm Field. The Company received $2.1 million in distributions from Tatex II during the six months ended June 30, 2019 , of which $1.9 million related to proceeds from the sale of its interest in APICO. Grizzly Oil Sands ULC The Company, through its wholly owned subsidiary Grizzly Holdings Inc. (“Grizzly Holdings”), owns an approximate 24.9999% 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 June 30, 2019 , Grizzly had approximately 830,000 acres under lease in the Athabasca, Peace River and Cold Lake oil sands regions of Alberta, Canada. The Company reviewed its investment in Grizzly for impairment at June 30, 2019 and 2018 and determined no impairment was required. If commodity prices decline in the future however, impairment of the Company's investment in Grizzly may be necessary. During the six months ended June 30, 2019 , Gulfport paid $0.4 million in cash calls. Grizzly’s functional currency is the Canadian dollar. The Company’s investment in Grizzly was increased by $3.5 million and $7.3 million for the three and six months ended June 30, 2019 , respectively, as a result of a foreign currency translation gain. The Company's investment in Grizzly was decreased by $3.4 million and $8.7 million for the three and six months ended June 30, 2018 , respectively, as a result of a foreign currency translation loss. Timber Wolf Terminals LLC During 2012, the Company invested in Timber Wolf. Timber Wolf was formed to operate a crude/condensate terminal and a sand transloading facility in Ohio. Timber Wolf was dissolved in 2018. Windsor Midstream LLC At June 30, 2019 , the Company held a 22.5% interest in Windsor Midstream LLC (“Midstream”), an entity controlled and managed by an unrelated third party. The Company received no distributions from Midstream during the six months ended June 30, 2019 . As of June 30, 2019 , the Company determined that Midstream was a variable interest entity ("VIE") but was not the primary beneficiary because it does not have a controlling financial interest in Midstream. This entity is considered a VIE because the limited partners lack substantive kick-out or participating rights over the general partner. The general partner has power to direct the activities that most significantly impact Midstream's economic performance. The Company accounts for its investment in VIEs following the equity method of accounting. The carrying amounts of the Company’s equity investments are classified as other non-current assets on the accompanying consolidated balance sheets. The Company’s maximum exposure to loss as a result of its involvement with VIEs is based on the Company’s capital contributions and the economic performance of the VIEs, and is equal to the carrying value of the Company’s investments which is the maximum loss the Company could be required to record in the consolidated statements of operations Mammoth Energy Services, Inc. At June 30, 2019 , the Company owned 9,829,548 shares, or approximately 21.8% , of the outstanding common stock of Mammoth Energy Services, Inc. ("Mammoth Energy"). The Company reviewed its investment in Mammoth Energy as of June 30, 2019 for impairment based on certain qualitative and quantitative factors. As a result of the calculated fair values and other qualitative factors, the Company concluded that an other than temporary impairment was indicated. This resulted in recording an aggregate impairment loss of $125.4 million for the six months ended June 30, 2019 , which is included in loss (income) from equity method investments, net in the accompanying consolidated statements of operations. If Mammoth Energy's common stock continues to trade below the Company's carrying value for a prolonged period of time, further impairment of the Company's investment in Mammoth Energy may be necessary. The Company’s investment in Mammoth Energy was increased by $0.1 million and $0.2 million foreign currency gains res ulting from Mammoth Energy's foreign subsidiary for the three and six months ended June 30, 2019 , respectively. The Company’s investment in Mammoth Energy was decreased by a $0.1 million and $0.3 million foreign currency loss resulting from Mammoth Energy’s foreign subsidiary for the three and six months ended June 30, 2018 , respectively. During the six months ended June 30, 2019 , Gulfport received distributions of $2.5 million from Mammoth Energy as a result of $0.125 per share dividends in February 2019 and May 2019. The approximate fair value of the Company's investment in Mammoth Energy's common stock at June 30, 2019 was $67.7 million based on the quoted market price of Mammoth Energy's common stock. The loss (income) from equity method investments presented in the table above reflects any intercompany profit eliminations. Strike Force Midstream LLC In February 2016, the Company, through its wholly owned subsidiary Gulfport Midstream Holdings, LLC (“Midstream Holdings”), entered into an agreement with Rice Midstream Holdings LLC (“Rice”), then a subsidiary of Rice Energy Inc., to develop natural gas gathering assets in eastern Belmont County and Monroe County, Ohio through Strike Force. In 2017, Rice was acquired by EQT Corporation ("EQT"). The Company owned a 25%

LONG-TERM DEBT

LONG-TERM DEBT	6 Months Ended
	Jun. 30, 2019
Long-term Debt, Unclassified [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Long-term debt consisted of the following items as of June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 (In thousands) Revolving credit agreement (1) $ 155,000 $ 45,000 6.625% senior unsecured notes due 2023 350,000 350,000 6.000% senior unsecured notes due 2024 650,000 650,000 6.375% senior unsecured notes due 2025 600,000 600,000 6.375% senior unsecured notes due 2026 450,000 450,000 Net unamortized debt issuance costs (2) (28,426 ) (30,733 ) Construction loan 22,719 23,149 Less: current maturities of long term debt (615 ) (651 ) Debt reflected as long term $ 2,198,678 $ 2,086,765 (1) The Company has entered into a senior secured revolving credit facility, as amended (the "revolving credit facility"), with The Bank of Nova Scotia, as the lead arranger and administrative agent and other lenders. On June 3, 2019, the Company further amended its revolving credit facility to, among other things, allow the Company to designate certain of its subsidiaries as unrestricted subsidiaries and to include LIBOR replacement provisions. Additionally, the borrowing base was reaffirmed at $1.4 billion , and the Company’s elected commitment amount remained at $1.0 billion . As of June 30, 2019 , $155.0 million was outstanding under the revolving credit facility and the total availability for future borrowings under this facility, after giving effect to an aggregate of $251.5 million letters of credit, was $593.5 million . The Company’s wholly owned subsidiaries have guaranteed the obligations of the Company under the revolving credit facility. At June 30, 2019 , amounts borrowed under the revolving credit facility bore interest at a weighted average rate of 3.93% . The Company was in compliance with its financial covenants under the revolving credit facility at June 30, 2019 . (2) Loan issuance costs related to the 6.625% Senior Notes due 2023 (the "2023 Notes"), the 6.000% Senior Notes due 2024 (the "2024 Notes"), the 6.375% Senior Notes due 2025 (the "2025 Notes") and the 6.375% Senior Notes due 2026 (the "2026 Notes") (collectively the “Notes”) have been presented as a reduction to the Notes. At June 30, 2019 , total unamortized debt issuance costs were $4.0 million for the 2023 Notes, $8.1 million for the 2024 Notes, $11.7 million for the 2025 Notes and $4.7 million for the 2026 Notes. In addition, loan commitment fee costs for the Company's construction loan agreement were $0.1 million at June 30, 2019 . The Company capitalized approximately $1.0 million and $1.8 million in interest expense to undeveloped oil and natural gas properties during the three and six months ended June 30, 2019 , respectively. The Company capitalized approximately $1.5 million and $2.4 million in interest expense to undeveloped oil and natural gas properties during the three and six months ended June 30, 2018 , respectively.

COMMON STOCK AND CHANGES IN CAP

COMMON STOCK AND CHANGES IN CAPITALIZATION	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
COMMON STOCK AND CHANGES IN CAPITALIZATION	COMMON STOCK AND CHANGES IN CAPITALIZATION Stock Repurchase Program In January 2018, the board of directors of the Company approved a stock repurchase program to acquire up to $100 million of the Company's outstanding stock during 2018. In May 2018, the Company's board of directors authorized the expansion of its stock repurchase program, authorizing the Company to acquire up to an additional $100 million of its outstanding common stock during 2018 for a total of up to $200 million . The repurchase program did not require the Company to acquire any specific number of shares. This repurchase program was authorized to extend through December 31, 2018 and the Company repurchased 20.7 million shares of common stock in 2018 for $200.0 million in aggregate consideration. In January 2019, the board of directors of the Company approved a new stock repurchase program to acquire up to $400 million of the Company's outstanding common stock within a 24 month period. Purchases under the repurchase program may be made from time to time in open market or privately negotiated transactions, and are subject to market conditions, applicable legal requirements, contractual obligations and other factors. The repurchase program does not require the Company to acquire any specific number of shares. This repurchase program is authorized to extend through December 31, 2020 and may be suspended, modified, extended or discontinued by the board of directors at any time. The Company repurchased approximately 0.2 million and 3.8 million shares for a cost of approximately $1.8 million and $30.0 million during the three and six months ended June 30, 2019 , respectively. Additionally, during each of the three and six months ended June 30, 2019 , the Company repurchased approximately 0.1 million shares for a cost of approximately $0.5 million and $0.6 million

STOCK-BASED COMPENSATION

STOCK-BASED COMPENSATION	6 Months Ended
	Jun. 30, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION The Company has granted restricted stock units to employees and directors pursuant to the 2013 Restated Incentive Stock Plan ("2013 Plan"), as discussed below. During the three and six months ended June 30, 2019 , the Company’s stock-based compensation cost was $2.8 million and $5.6 million , respectively, of which the Company capitalized $1.1 million and $2.3 million , respectively, relating to its exploration and development efforts. During the three and six months ended June 30, 2018 , the Company's stock-based compensation cost was $3.3 million and $6.0 million , respectively, of which the Company capitalized $1.3 million and $2.4 million , respectively, relating to its exploration and development efforts. Stock compensation costs, net of the amounts capitalized, are included in general and administrative expenses in the accompanying consolidated statements of operations. The following table summarizes restricted stock unit activity for the six months ended June 30, 2019 : Number of Unvested Restricted Stock Units Weighted Average Grant Date Fair Value Number of Unvested Performance Vesting Restricted Stock Units Weighted Average Grant Date Fair Value Unvested shares as of January 1, 2019 1,535,811 $ 11.57 $ — $ — Granted 770,661 6.96 228,659 9.66 Vested (325,193 ) 10.08 — — Forfeited (8,776 ) 12.44 — — Unvested shares as of June 30, 2019 1,972,503 $ 10.01 228,659 $ 9.66 Restricted Stock Units Restricted stock units awarded under the 2013 Plan generally vest over a period of one year in the case of directors and three years in the case of employees and vesting is dependent upon the recipient meeting applicable service requirements. Stock-based compensation costs are recorded ratably over the service period. The grant date fair value of restricted stock units represents the closing market price of the Company's common stock on the date of grant. Unrecognized compensation expense as of June 30, 2019 related to restricted stock units was $13.8 million . The expense is expected to be recognized over a weighted average period of 1.90 years. Performance Vesting Restricted Stock Units During the six months ended June 30, 2019 , the Company awarded performance vesting units to its Chief Executive Officer under the 2013 Plan. The number of shares of common stock that will ultimately be issued will be determined by comparing the Company's total stockholder return relative to the total stockholder return of a predetermined group of peer companies at the end of the 36-month performance period. The grant date fair value was determined using the Monte Carlo simulation method and is being recorded ratably over the performance period. Expected volatilities utilized in the Monte Carlo model were estimated using a historical period consistent with the remaining performance period of approximately three years . The risk-free interest rate was based on the U.S. Treasury rate for a term commensurate with the expected life of the grant. The Company assumed a risk-free interest rate of 2.42% and a range of expected volatilities of 30.5% to 72.6% to estimate the fair value of performance vesting units granted during the six months ended June 30, 2019 . Unrecognized compensation expense as of June 30, 2019 related to performance vesting restricted shares was $1.9 million . The expense is expected to be recognized over a weighted average period of 2.51 years.

EARNINGS PER SHARE

EARNINGS PER SHARE	6 Months Ended
	Jun. 30, 2019
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 June 30, 2019 2018 Income Shares Per Share Income Shares Per Share (In thousands, except share data) Basic: Net income $ 234,956 159,324,909 $ 1.47 $ 111,319 173,623,630 $ 0.64 Effect of dilutive securities: Stock options and awards — 181,917 — 516,997 Diluted: Net income $ 234,956 159,506,826 $ 1.47 $ 111,319 174,140,627 $ 0.64 Six months ended June 30, 2019 2018 Income Shares Per Income Shares Per (In thousands, except share data) Basic: Net income $ 297,198 161,064,787 $ 1.85 $ 201,409 177,158,230 $ 1.14 Effect of dilutive securities: Stock options and awards — 525,300 — 579,052 Diluted: Net income $ 297,198 161,590,087 $ 1.84 $ 201,409 177,737,282 $ 1.13

COMMITTMENTS AND CONTINGENCIES

COMMITTMENTS AND CONTINGENCIES	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Firm Transportation and Sales Commitments The table below presents the firm sales commitments by year: (MMBtu per day) Remaining 2019 493,000 2020 276,000 2021 179,000 2022 70,000 2023 42,000 Thereafter 25,000 Total 1,085,000 The table below presents the firm transportation commitments by year: (In thousands) Remaining 2019 $ 122,128 2020 273,973 2021 273,011 2022 273,011 2023 268,209 Thereafter 2,283,229 Total $ 3,493,561 Other Commitments Effective October 1, 2014, the Company entered into a Sand Supply Agreement with Muskie Proppant LLC (“Muskie”), a subsidiary of Mammoth Energy and a related party. Pursuant to this agreement, as amended effective August 3, 2018, the Company has agreed to purchase annual and monthly amounts of proppant sand subject to exceptions specified in the agreement at agreed pricing plus agreed costs and expenses through 2021. 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 no t incur any non-utilization fees under this agreement during the three months ended June 30, 2019 and incurred $0.3 million of such fees during the six months ended June 30, 2019 . The Company did no t incur any non-utilization fees during the three months ended June 30, 2018 and incurred $0.9 million of such fees during the six months ended June 30, 2018 . Future minimum commitments under this agreement at June 30, 2019 are: (In thousands) Remaining 2019 $ 12,000 2020 24,000 2021 24,000 Total $ 60,000 Litigation and Regulatory Proceedings The Company is involved in a number of litigation and regulatory proceedings including those described below. Many of these proceedings are in early stages, and many of them seek or may seek damages and penalties, the amount of which is indeterminate. The Company's total accrued liabilities in respect of litigation and regulatory proceedings is determined on a case-by-case basis and represents an estimate of probable losses after considering, among other factors, the progress of each case or proceeding, its experience and the experience of others in similar cases or proceedings, and the opinions and views of legal counsel. Significant judgment is required in making these estimates and their final liabilities may ultimately be materially different. The Company, along with a number of other oil and gas companies, has been named as a defendant in two separate complaints, one filed by the State of Louisiana and the Parish of Cameron in the 38th Judicial District Court for the Parish of Cameron on February 9, 2016 and the other filed by the State of Louisiana and the District Attorney for the 15 th Judicial District of the State of Louisiana in the 15 th Judicial District Court for the Parish of Vermilion on July 29, 2016 (together, the "Complaints"). The Complaints allege that certain of the defendants’ operations violated the State and Local Coastal Resources Management Act of 1978, as amended, and the rules, regulations, orders and ordinances adopted thereunder (the "CZM Laws") by causing substantial damage to land and waterbodies located in the coastal zone of the relevant Parish. The plaintiffs seek damages and other appropriate relief under the CZM Laws, including the payment of costs necessary to clear, re-vegetate, detoxify and otherwise restore the affected coastal zone of the relevant Parish to its original condition, actual restoration of such coastal zone to its original condition, and the payment of reasonable attorney fees and legal expenses and interest. The cases have been removed to the United States District Court for the Western District of Louisiana, and motions to remand are pending. The cases are still in their early stages and the parties have conducted very little discovery. As a result, the Company has not had the opportunity to evaluate the applicability of the allegations made in plaintiffs' complaints to the Company's operations and management cannot determine the amount of loss, if any, that may result. SEC Investigation The SEC has commenced an investigation with respect to certain actions by former Company management, including alleged improper personal use of Company assets, and potential violations by former management and the Company of the Sarbanes-Oxley Act of 2002 in connection with such actions. The Company has fully cooperated and intends to continue to cooperate fully with the SEC’s investigation. Although it is not possible to predict the ultimate resolution or financial liability with respect to this matter, the Company believes that the outcome of this matter will not have a material effect on the Company’s business, financial condition or results of operations. Business Operations The Company is involved in various lawsuits and disputes incidental to its business operations, including commercial disputes, personal injury claims, royalty claims, property damage claims and contract actions. Environmental Contingencies The nature of the oil and gas business carries with it certain environmental risks for Gulfport and its subsidiaries. They have implemented various policies, programs, procedures, training and audits to reduce and mitigate such environmental risks. They conduct periodic reviews, on a company-wide basis, to assess changes in their environmental risk profile. Environmental reserves are established for environmental liabilities for which economic losses are probable and reasonably estimable. The Company manages its exposure to environmental liabilities in acquisitions by using an evaluation process that seeks to identify pre-existing contamination or compliance concerns and address the potential liability. Depending on the extent of an identified environmental concern, they may, among other things, exclude a property from the transaction, require the seller to remediate the property to their satisfaction in an acquisition or agree to assume liability for the remediation of the property. The Company received several Finding of Violation (“FOVs”) from the United States Environmental Protection Agency ("USEPA") alleging violations of the Clean Air Act at approximately 12 locations in Ohio. The first FOV for one site was dated December 11, 2013. Two subsequent FOVs incorporated and expanded the scope on January 4, 2017 and April 15, 2019. The Company has exchanged information with the USEPA and is engaged in discussions aimed at resolving the allegations. Resolution of the matter may result in monetary sanctions of more than $100,000 . Other Matters Based on management’s current assessment, they are of the opinion that no pending or threatened lawsuit or dispute relating to its business operations is likely to have a material adverse effect on their future consolidated financial position, results of operations or cash flows. The final resolution of such matters could exceed amounts accrued, however, and actual results could differ materially from management’s estimates.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	6 Months Ended
	Jun. 30, 2019
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS Natural Gas, Oil and Natural Gas Liquids Derivative Instruments The Company seeks to reduce its exposure to unfavorable changes in natural gas, oil and natural gas liquids ("NGLs") prices, which are subject to significant and often volatile fluctuation, by entering into over-the-counter fixed price swaps, basis swaps and various types of option contracts. These contracts allow the Company to predict with greater certainty the effective natural gas, oil and NGLs 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. Fixed price swaps are settled monthly based on differences between the fixed price specified in the contract and the referenced settlement price. When the referenced settlement price is less than the price specified in the contract, the Company receives an amount from the counterparty based on the price difference multiplied by the volume. Similarly, when the referenced settlement price exceeds the price specified in the contract, the Company pays the counterparty an amount based on the price difference multiplied by the volume. The prices contained in these fixed price swaps are based on the NYMEX Henry Hub for natural gas, the NYMEX West Texas Intermediate for oil and Mont Belvieu for propane, pentane and ethane. Below is a summary of the Company’s open fixed price swap positions as of June 30, 2019 . Location Daily Volume (MMBtu/day) Weighted Remaining 2019 NYMEX Henry Hub 1,380,000 $ 2.81 2020 NYMEX Henry Hub 204,000 $ 2.77 Location Daily Volume Weighted Remaining 2019 NYMEX WTI 6,000 $ 60.81 2020 NYMEX WTI 6,000 $ 59.82 Location Daily Volume Weighted Remaining 2019 Mont Belvieu C2 1,000 $ 18.48 Remaining 2019 Mont Belvieu C3 4,000 $ 29.02 Remaining 2019 Mont Belvieu C5 1,000 $ 53.71 The Company sold call options and used the associated premiums to enhance the fixed price for a portion of the fixed price natural gas swaps listed above. Each short call option has an established ceiling price. When the referenced settlement price is above the price ceiling established by these short call options, the Company pays its counterparty an amount equal to the difference between the referenced settlement price and the price ceiling multiplied by the hedged contract volumes. Location Daily Volume (MMBtu/day) Weighted Average Price Remaining 2019 NYMEX Henry Hub 30,000 $ 3.10 For a portion of the natural gas fixed price swaps listed above, the counterparty had the option to extend the original terms for an additional twelve months for the period of January 2019 through December 2019. In December 2018, the counterparties chose to exercise all natural gas fixed price swaps, resulting in an additional 100,000 MMBtu per day at a weighted average price of $3.05 per MMBtu, which is included in the natural gas fixed price swaps listed above. In addition, the Company entered into natural gas basis swap positions. As of June 30, 2019 , the Company had the following natural gas basis swap positions open: Gulfport Pays Gulfport Receives Daily Volume (MMBtu/day) Weighted Average Fixed Spread Remaining 2019 Transco Zone 4 NYMEX Plus Fixed Spread 60,000 $ (0.05 ) 2020 Transco Zone 4 NYMEX Plus Fixed Spread 60,000 $ (0.05 ) 2020 Fixed Spread ONEOK Minus NYMEX 10,000 $ (0.54 ) Balance Sheet Presentation The Company reports the fair value of derivative instruments on the consolidated balance sheets as derivative instruments under current assets, noncurrent assets, current liabilities and noncurrent liabilities on a gross basis. The Company determines the current and noncurrent classification based on the timing of expected future cash flows of individual trades. The following table presents the fair value of the Company’s derivative instruments on a gross basis at June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 (In thousands) Short-term derivative instruments - asset $ 134,920 $ 21,352 Long-term derivative instruments - asset $ 5,036 $ — Short-term derivative instruments - liability $ 198 $ 20,401 Long-term derivative instruments - liability $ 210 $ 13,992 Gains and Losses The following table presents the gain and loss recognized in net gain (loss) on natural gas, oil and NGL derivatives in the accompanying consolidated statements of operations for the three and six months ended June 30, 2019 and 2018 . Net gain (loss) on derivative instruments Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (In thousands) Natural gas derivatives $ 152,475 $ (31,194 ) $ 136,044 $ (40,890 ) Oil derivatives 11,871 (24,419 ) 11,417 (33,566 ) NGL derivatives 6,794 (14,932 ) 3,634 (12,618 ) Total $ 171,140 $ (70,545 ) $ 151,095 $ (87,074 ) Offsetting of Derivative Assets and Liabilities As noted above, the Company records the fair value of derivative instruments on a gross basis. The following table presents the gross amounts of recognized derivative assets and liabilities in the consolidated balance sheets and the amounts that are subject to offsetting under master netting arrangements with counterparties, all at fair value. As of June 30, 2019 Gross Assets (Liabilities) Gross Amounts Presented in the Subject to Master Net Consolidated Balance Sheets Netting Agreements Amount (In thousands) Derivative assets $ 139,956 $ (408 ) $ 139,548 Derivative liabilities $ (408 ) $ 408 $ — As of December 31, 2018 Gross Assets (Liabilities) Gross Amounts Presented in the Subject to Master Net Consolidated Balance Sheets Netting Agreements Amount (In thousands) Derivative assets $ 21,352 $ (19,289 ) $ 2,063 Derivative liabilities $ (34,393 ) $ 19,289 $ (15,104 ) Concentration of Credit Risk By using derivative instruments that are not traded on an exchange, the Company is exposed to the credit risk of its counterparties. Credit risk is the risk of loss from counterparties not performing under the terms of the derivative instrument. When the fair value of a derivative instrument is positive, the counterparty is expected to owe the Company, which creates credit risk. To minimize the credit risk in derivative instruments, it is the Company’s policy to enter into derivative contracts only with counterparties that are creditworthy financial institutions deemed by management as competent and competitive market makers. The Company’s derivative contracts are with multiple counterparties to lessen its exposure to any individual counterparty. Additionally, the Company uses master netting agreements to minimize credit risk exposure. The creditworthiness of the Company’s counterparties is subject to periodic review. None of the Company’s derivative instrument contracts contain credit-risk related contingent features. Other than as provided by the Company’s revolving credit facility, the Company is not required to provide credit support or collateral to any of its counterparties under its derivative instruments, nor are the counterparties required to provide credit support to the Company.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	6 Months Ended
	Jun. 30, 2019
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. Fair value is 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. Market or observable inputs are the preferred sources of values, followed by assumptions based on hypothetical transactions in the absence of market inputs. Fair value measurements are 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. Valuation techniques that maximize the use of observable inputs are favored. Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement of assets and liabilities within the levels of the fair value hierarchy. Reclassifications of fair value between Level 1, Level 2 and Level 3 of the fair value hierarchy, if applicable, are made at the end of each quarter. The following tables summarize the Company’s financial and non-financial assets and liabilities by valuation level as of June 30, 2019 and December 31, 2018 : June 30, 2019 Level 1 Level 2 Level 3 (In thousands) Assets: Derivative Instruments $ — $ 139,956 $ — Liabilities: Derivative Instruments $ — $ 408 $ — December 31, 2018 Level 1 Level 2 Level 3 (In thousands) Assets: Derivative Instruments $ — $ 21,352 $ — Liabilities: Derivative Instruments $ — $ 34,393 $ — The Company estimates the fair value of all derivative instruments using industry-standard models that consider various assumptions, including current market and contractual prices for the underlying instruments, implied volatility, time value, nonperformance risk, as well as other relevant economic measures. Substantially all of these inputs are observable in the marketplace throughout the full term of the instrument and can be supported by observable data. The estimated fair values of proved oil and natural 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 natural 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. The asset retirement obligations assumed as part of the business combination were estimated using the same assumptions and methodology as described below. The fair value of the Company's investment in Mammoth Energy as of June 30, 2019 was estimated using Level 1 inputs, as the price per share was a quoted price in an active market for identical Mammoth Energy common shares. 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 1 for further discussion of the Company’s asset retirement obligations. Asset retirement obligations incurred during the six months ended June 30, 2019 were approximately $5.2 million .

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	6 Months Ended
	Jun. 30, 2019
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 Company's construction 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 June 30, 2019 , the carrying value of the outstanding debt represented by the Notes was approximately $2.0 billion , including the unamortized debt issuance cost of approximately $4.0 million related to the 2023 Notes, approximately $8.1 million related to the 2024 Notes, approximately $11.7 million related to the 2025 Notes and approximately $4.7 million related to the 2026 Notes. Based on the quoted market price, the fair value of the Notes was determined to be approximately $1.6 billion at June 30, 2019

REVENUE FROM CONTRACTS WITH CUS

REVENUE FROM CONTRACTS WITH CUSTOMERS	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
REVENUE FROM CONTRACTS WITH CUSTOMERS	REVENUE FROM CONTRACTS WITH CUSTOMERS Revenue Recognition The Company’s revenues are primarily derived from the sale of natural gas, oil and condensate and NGLs. Sales of natural gas, oil and condensate and NGLs are recognized in the period that the performance obligations are satisfied. The Company generally considers the delivery of each unit (MMBtu or Bbl) to be separately identifiable and represents a distinct performance obligation that is satisfied at the time control of the product is transferred to the customer. Revenue is measured based on consideration specified in the contract with the customer, and excludes any amounts collected on behalf of third parties. These contracts typically include variable consideration that is based on pricing tied to market indices and volumes delivered in the current month. As such, this market pricing may be constrained (i.e., not estimable) at the inception of the contract but will be recognized based on the applicable market pricing, which will be known upon transfer of the goods to the customer. The payment date is usually within 30 days of the end of the calendar month in which the commodity is delivered. A significant number of the Company's product sales are short-term in nature generally through evergreen contracts with contract terms of one year or less, and the Company's product sales that have a contractual term greater than one year have no long-term fixed consideration. Contract Balances Receivables from contracts with customers are recorded when the right to consideration becomes unconditional, generally when control of the product has been transferred to the customer. Receivables from contracts with customers were $131.7 million and $210.2 million as of June 30, 2019 and December 31, 2018 , respectively, and are reported in accounts receivable - oil and natural gas sales on the consolidated balance sheet. The Company currently has no assets or liabilities related to its revenue contracts, including no upfront or rights to deficiency payments. Prior-Period Performance Obligations The Company records revenue in the month production is delivered to the purchaser. However, settlement statements for certain sales may be received for 30 to 90 days after the date production is delivered, and as a result, the Company is required to estimate the amount of production that was delivered to the purchaser and the price that will be received for the sale of the product. The differences between the estimates and the actual amounts for product sales is recorded in the month that payment is received from the purchaser. For the six months ended June 30, 2019 , revenue recognized in the reporting period related to performance obligations satisfied in prior reporting periods was not material.

LEASES

LEASES	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
LEASES	LEASES Effective January 1, 2019, the Company adopted Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) . The new standard supersedes the previous lease guidance by requiring lessees to recognize a right-of-use asset and lease liability on the balance sheet for all leases with lease terms of greater than one year while maintaining substantially similar classifications for financing and operating leases. The Company adopted the new standard on a prospective basis using the simplified transition method permitted by ASU No. 2018-11, Leases (Topic 842): Targeted Improvements . Offsetting right-of-use assets and corresponding lease liabilities recognized by the Company on the adoption date totaled approximately $110 million , representing minimum payment obligations associated with identified leases with contractual durations exceeding one year. No cumulative-effect adjustment to retained earnings was required upon adoption of the new standard. The Company elected the package of practical expedients permitted under the new standard, which among other things, allows for lease and non-lease components in a contract to be accounted for as a single lease component for all asset classes and the carry forward of historical lease classifications. Nature of Leases The Company has operating leases associated with drilling rig commitments, pressure pumping services, field offices and other equipment with remaining lease terms with contractual durations in excess of one year. Short-term leases that have an initial term of one year or less are not capitalized. The Company has entered into contracts for drilling rigs with third parties to ensure rig availability in its key operating areas. The Company has concluded its drilling rig contracts are operating leases as the assets are identifiable and the evaluation that the Company has the right to control the identified assets. The Company's drilling rig commitments are typically structured with an initial term of one to two years and expire at various dates through 2021. These agreements typically include renewal options at the end of the initial term. Due to the nature of the Company's drilling schedules and potential volatility in commodity prices, the Company is unable to determine at commencement with reasonable certainty if the renewal options will be exercised; therefore, renewal options are not considered in the lease term for drilling contracts. The operating lease liabilities associated with these rig commitments are based on the minimum contractual obligations, primarily standby rates, and do not include variable amounts based on actual activity in a given period. Pursuant to the full cost method of accounting, these costs are capitalized as part of oil and natural gas properties on the accompanying consolidated balance sheets. A portion of these costs are borne by other interest owners. Effective October 1, 2014, the Company entered into an Amended and Restated Master Services Agreement for pressure pumping services with Stingray Pressure Pumping LLC (“Stingray Pressure”), a subsidiary of Mammoth Energy and a related party. Pursuant to this agreement, as amended effective July 1, 2018, Stingray Pressure has agreed to provide hydraulic fracturing, stimulation and related completion and rework services to the Company through 2021 and the Company has agreed to pay Stingray Pressure a monthly service fee plus the associated costs of the services provided. The Company has the right to suspend services of one crew and only one crew at any point in time without payment, fee or other obligation associated with the suspended crew, given appropriate notification of suspension. The Company has determined that the agreement with Stingray Pressure is an operating lease due to the implicit identification of assets and the evaluation that the Company has the right to control the identified assets. The operating lease liability associated with this agreement is based on the minimum contractual obligations, which is the monthly service fee for one crew, and does not include variable amounts based on actual activity in a given period. Pursuant to the full cost method of accounting, these costs are capitalized as part of oil and natural gas properties on the accompanying consolidated balance sheets. A portion of these costs are borne by other interest owners. The Company rents office space for its field locations and certain other equipment from third parties, which expire at various dates through 2024. These agreements are typically structured with non-cancelable terms of one to five years . The Company has determined these agreements represent operating leases with a lease term that equals the primary non-cancelable contract term. The Company has included any renewal options that it has determined are reasonably certain of exercise in the determination of the lease terms. Discount Rate As most of the Company's leases do not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. The Company's incremental borrowing rate reflects the estimated rate of interest that it would pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Maturities of operating lease liabilities as of June 30, 2019 were as follows: (In thousands) Remaining 2019 $ 25,243 2020 27,481 2021 22,731 2022 115 2023 90 Thereafter 30 Total lease payments $ 75,690 Less: Imputed interest (2,777 ) Total $ 72,913 Lease cost for the six months ended June 30, 2019 consisted of the following: (In thousands) Operating lease cost $ 16,284 Operating lease cost - related party 11,220 Variable lease cost 960 Variable lease cost - related party 59,611 Short-term lease cost 183 Total lease cost (1) $ 88,258 (1) The majority of the Company's total lease cost was capitalized to the full cost pool, and the remainder was included in general and administrative expenses in the accompanying consolidated statement of operations. Supplemental cash flow information for the six months ended June 30, 2019 related to leases was as follows: Cash paid for amounts included in the measurement of lease liabilities (In thousands) Operating cash flows from operating leases $ 120 Investing cash flow from operating leases $ 12,288 Investing cash flow from operating leases - related party $ 43,925 The weighted-average remaining lease term as of June 30, 2019 was 1.86 years. The weighted-average discount rate used to determine the operating lease liability as of June 30, 2019 was 3.78%

INCOME TAXES

INCOME TAXES	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The Company records its quarterly tax provision based on an estimate of the annual effective tax rate expected to apply to continuing operations for the various jurisdictions in which it operates. The tax effects of certain items, such as tax rate changes, significant unusual or infrequent items, and certain changes in the assessment of the realizability of deferred taxes, are recognized as discrete items in the period in which they occur and are excluded from the estimated annual effective tax rate. The Company’s ability to utilize NOL carryforwards and other tax attributes to reduce future federal taxable income is subject to potential limitations under Internal Revenue Code Section 382 (“Section 382”) and its related tax regulations. The utilization of these attributes may be limited if certain ownership changes by 5% stockholders (as defined in Treasury regulations pursuant to Section 382) and the effects of stock issuances by the Company during any three-year period result in a cumulative change of more than 50% in the beneficial ownership of Gulfport. The Company updates its Section 382 analysis to determine if an ownership change has occurred at each reporting period. If it is determined that an ownership change has occurred under these rules, the Company would generally be subject to an annual limitation on the use of pre-ownership change NOL carryforwards and certain other losses and/or credits. In addition, certain future transactions regarding the Company's equity, including the cumulative effects of small transactions as well as transactions beyond the Company’s control, could cause an ownership change and therefore a potential limitation on the annual utilization of its deferred tax assets. For the three and six months ended June 30, 2019 , the Company's estimated annual effective tax rates were approximately (322.5)% and (152.2)% , respectively. The change is primarily due to the release of the valuation allowance that was previously recorded against deferred tax assets of $179.3 million as a discrete adjustment in the quarter. The Company considered the release of the valuation allowance resulting from current period earnings in the estimated annual effective tax rate and recognized the tax benefit associated with future earnings as a discrete item. For the three month period ended March 31, 2019, the Company maintained a full valuation allowance against its deferred tax assets based on its conclusion, considering all available evidence (both positive and negative), that it was more likely than not that the deferred tax assets would not be realized. A valuation allowance for deferred tax assets, including net operating losses, is recognized when it is more likely than not that some or all of the benefit from the deferred tax assets will not be realized. To assess that likelihood, the Company uses estimates and judgment regarding future taxable income, and considers the tax laws in the jurisdiction where such taxable income is generated, to determine whether a valuation allowance is required. Such evidence can include current financial position, results of operations, both actual and forecasted, the reversal of deferred tax liabilities and tax planning strategies as well as the current and forecasted business economics of the oil and gas industry. As of each reporting date, management considers new evidence, both positive and negative, that could affect its view of the future realization of deferred tax assets. As of June 30, 2019, in part because in the current year the Company achieved more than three years of cumulative pretax income in the U.S. federal tax jurisdiction and the Company determined that an ownership change under Internal Revenue Code Section 382 did not occur that would further limit its ability to utilize net operating loss carryforwards, management determined that there was sufficient positive evidence to conclude that it is more likely than not that additional deferred taxes of $207.2 million are realizable. The Company will recognize $27.7 million of valuation allowance release as part of its estimated annualized effective tax rate and $179.3 million as a discrete adjustment during the six month period ending June 30, 2019. It therefore reduced the valuation allowance accordingly. The Company maintained a valuation allowance of $4.8 million

CONDENSED CONSOLIDATING FINANCI

CONDENSED CONSOLIDATING FINANCIAL INFORMATION	6 Months Ended
	Jun. 30, 2019
Condensed Financial Information Disclosure [Abstract]
CONDENSED CONSOLIDATING FINANCIAL INFORMATION	CONDENSED CONSOLIDATING FINANCIAL INFORMATION The 2023 Notes, the 2024 Notes, the 2025 Notes and the 2026 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 or Mule Sky LLC ("Mule Sky") (the “Non-Guarantors”). 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. Effective June 1, 2019, the Parent contributed interests in certain oil and gas assets and related liabilities to certain of the Guarantors. The following condensed consolidating balance sheets, statements of operations, statements of comprehensive income and statements of cash flows are provided for the Parent, the Guarantors and the Non-Guarantors 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-Guarantors. CONDENSED CONSOLIDATING BALANCE SHEETS (Amounts in thousands) June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 10,940 $ 9,799 $ 38 $ — $ 20,777 Accounts receivable - oil and natural gas sales 4,116 127,559 — — 131,675 Accounts receivable - joint interest and other 9,043 37,602 — — 46,645 Accounts receivable - intercompany 819,584 433,776 — (1,253,360 ) — Prepaid expenses and other current assets 5,948 3,451 75 — 9,474 Short-term derivative instruments 134,920 — — — 134,920 Total current assets 984,551 612,187 113 (1,253,360 ) 343,491 Property and equipment: Oil and natural gas properties, full-cost accounting 1,352,894 9,158,193 69 (729 ) 10,510,427 Other property and equipment 92,343 751 3,319 — 96,413 Accumulated depletion, depreciation, amortization and impairment (1,414,011 ) (3,468,663 ) (55 ) — (4,882,729 ) Property and equipment, net 31,226 5,690,281 3,333 (729 ) 5,724,111 Other assets: Equity investments and investments in subsidiaries 5,171,925 — 51,607 (5,104,225 ) 119,307 Long-term derivative instruments 5,036 — — — 5,036 Deferred tax asset 179,331 — — — 179,331 Inventories 188 8,813 — — 9,001 Operating lease assets 19,334 — — — 19,334 Operating lease assets - related parties 53,579 — — — 53,579 Other assets 11,682 598 — — 12,280 Total other assets 5,441,075 9,411 51,607 (5,104,225 ) 397,868 Total assets $ 6,456,852 $ 6,311,879 $ 55,053 $ (6,358,314 ) $ 6,465,470 Liabilities and Stockholders ’ Equity Current liabilities: Accounts payable and accrued liabilities $ 74,597 $ 419,190 $ 43 $ — $ 493,830 Accounts payable - intercompany 469,071 780,600 3,689 (1,253,360 ) — Short-term derivative instruments 198 — — — 198 Current portion of operating lease liabilities 17,999 — — — 17,999 Current portion of operating lease liabilities - related parties 20,817 — — — 20,817 Current maturities of long-term debt 615 — — — 615 Total current liabilities 583,297 1,199,790 3,732 (1,253,360 ) 533,459 Long-term derivative instruments 210 — — — 210 Asset retirement obligation - long-term 30,035 58,456 — — 88,491 Deferred tax liability 3,127 — — — 3,127 Non-current operating lease liabilities 1,335 — — — 1,335 Non-current operating lease liabilities - related parties 32,762 — — — 32,762 Long-term debt, net of current maturities 2,198,678 — — — 2,198,678 Total liabilities 2,849,444 1,258,246 3,732 (1,253,360 ) 2,858,062 Stockholders’ equity: Common stock 1,594 — — — 1,594 Paid-in capital 4,202,599 4,170,574 262,059 (4,432,633 ) 4,202,599 Accumulated other comprehensive loss (48,615 ) — (46,527 ) 46,527 (48,615 ) (Accumulated deficit) retained earnings (548,170 ) 883,059 (164,211 ) (718,848 ) (548,170 ) Total stockholders’ equity 3,607,408 5,053,633 51,321 (5,104,954 ) 3,607,408 Total liabilities and stockholders ’ equity $ 6,456,852 $ 6,311,879 $ 55,053 $ (6,358,314 ) $ 6,465,470 CONDENSED CONSOLIDATING BALANCE SHEETS (Amounts in thousands) December 31, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 25,585 $ 26,711 $ 1 $ — $ 52,297 Accounts receivable - oil and natural gas sales 146,075 64,125 — — 210,200 Accounts receivable - joint interest and other 16,212 6,285 — — 22,497 Accounts receivable - intercompany 671,633 319,464 — (991,097 ) — Prepaid expenses and other current assets 8,433 2,174 — — 10,607 Short-term derivative instruments 21,352 — — — 21,352 Total current assets 889,290 418,759 1 (991,097 ) 316,953 Property and equipment: Oil and natural gas properties, full-cost accounting, 7,044,550 2,983,015 — (729 ) 10,026,836 Other property and equipment 91,916 751 — — 92,667 Accumulated depletion, depreciation, amortization and impairment (4,640,059 ) (39 ) — — (4,640,098 ) Property and equipment, net 2,496,407 2,983,727 — (729 ) 5,479,405 Other assets: Equity investments and investments in subsidiaries 2,856,988 — 44,259 (2,665,126 ) 236,121 Inventories 3,620 1,134 — — 4,754 Other assets 12,624 1,178 — 1 13,803 Total other assets 2,873,232 2,312 44,259 (2,665,125 ) 254,678 Total assets $ 6,258,929 $ 3,404,798 $ 44,260 $ (3,656,951 ) $ 6,051,036 Liabilities and Stockholders ’ Equity Current liabilities: Accounts payable and accrued liabilities $ 419,107 $ 99,273 $ — $ — $ 518,380 Accounts payable - intercompany 320,259 670,708 130 (991,097 ) — Short-term derivative instruments 20,401 — — — 20,401 Current maturities of long-term debt 651 — — — 651 Total current liabilities 760,418 769,981 130 (991,097 ) 539,432 Long-term derivative instruments 13,992 — — — 13,992 Asset retirement obligation - long-term 66,859 13,093 — — 79,952 Deferred tax liability 3,127 — — — 3,127 Long-term debt, net of current maturities 2,086,765 — — — 2,086,765 Total liabilities 2,931,161 783,074 130 (991,097 ) 2,723,268 Stockholders’ equity: Common stock 1,630 — — — 1,630 Paid-in capital 4,227,532 1,915,598 261,626 (2,177,224 ) 4,227,532 Accumulated other comprehensive loss (56,026 ) — (53,783 ) 53,783 (56,026 ) (Accumulated deficit) retained earnings (845,368 ) 706,126 (163,713 ) (542,413 ) (845,368 ) Total stockholders’ equity 3,327,768 2,621,724 44,130 (2,665,854 ) 3,327,768 Total liabilities and stockholders ’ equity $ 6,258,929 $ 3,404,798 $ 44,260 $ (3,656,951 ) $ 6,051,036 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Three months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Total revenues $ 280,291 $ 178,703 $ — $ — $ 458,994 Costs and expenses: Lease operating expenses 12,256 10,132 — — 22,388 Production taxes 2,820 5,278 — — 8,098 Midstream gathering and processing expenses 28,121 43,894 — — 72,015 Depreciation, depletion and amortization 80,132 44,764 55 — 124,951 General and administrative expenses 16,745 (3,583 ) 103 — 13,265 Accretion expense 438 921 — — 1,359 140,512 101,406 158 — 242,076 INCOME (LOSS) FROM OPERATIONS 139,779 77,297 (158 ) — 216,918 OTHER EXPENSE (INCOME): Interest expense 35,835 (955 ) — — 34,880 Interest income (120 ) (39 ) — — (159 ) Insurance proceeds (83 ) — — — (83 ) Loss (income) from equity method investments and investments in subsidiaries 47,449 — (54 ) 78,187 125,582 Other expense 1,073 — — — 1,073 84,154 (994 ) (54 ) 78,187 161,293 INCOME (LOSS) BEFORE INCOME TAXES 55,625 78,291 (104 ) (78,187 ) 55,625 INCOME TAX BENEFIT (179,331 ) — — — (179,331 ) NET INCOME (LOSS) $ 234,956 $ 78,291 $ (104 ) $ (78,187 ) $ 234,956 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Three months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Total revenues $ 146,774 $ 105,966 $ — $ — $ 252,740 Costs and expenses: Lease operating expenses 16,593 6,319 — — 22,912 Production taxes 4,793 2,866 — — 7,659 Midstream gathering and processing expenses 52,542 18,898 — — 71,440 Depreciation, depletion and amortization 121,915 — — — 121,915 General and administrative expenses 14,975 (968 ) 1 — 14,008 Accretion expense 795 220 — — 1,015 211,613 27,335 1 — 238,949 (LOSS) INCOME FROM OPERATIONS (64,839 ) 78,631 (1 ) — 13,791 OTHER (INCOME) EXPENSE: Interest expense 34,663 (959 ) — — 33,704 Interest income (27 ) (6 ) — — (33 ) Insurance proceeds (231 ) — — — (231 ) Gain on sale of equity method investments (25,616 ) (96,419 ) — — (122,035 ) (Income) loss from equity method investments and investments in subsidiaries (183,901 ) (336 ) 228 175,121 (8,888 ) Other (income) expense (1,046 ) 1 — 1,000 (45 ) (176,158 ) (97,719 ) 228 176,121 (97,528 ) INCOME (LOSS) BEFORE INCOME TAXES 111,319 176,350 (229 ) (176,121 ) 111,319 INCOME TAX BENEFIT — — — — — NET INCOME (LOSS) $ 111,319 $ 176,350 $ (229 ) $ (176,121 ) $ 111,319 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Six months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Total revenues $ 466,537 $ 313,035 $ — $ — $ 779,572 Costs and expenses: Lease operating expenses 27,149 15,046 — — 42,195 Production taxes 6,081 9,938 — — 16,019 Midstream gathering and processing expenses 71,420 70,877 — — 142,297 Depreciation, depletion, and amortization 198,564 44,765 55 — 243,384 General and administrative expenses 28,977 (4,258 ) 104 — 24,823 Accretion expense 1,389 1,037 — — 2,426 333,580 137,405 159 — 471,144 INCOME (LOSS) FROM OPERATIONS 132,957 175,630 (159 ) — 308,428 OTHER EXPENSE (INCOME): Interest expense 70,259 (1,259 ) — — 69,000 Interest income (267 ) (44 ) — — (311 ) Insurance proceeds (83 ) — — — (83 ) (Income) loss from equity method investments and investments in subsidiaries (55,465 ) — 339 176,435 121,309 Other expense 646 — — — 646 15,090 (1,303 ) 339 176,435 190,561 INCOME (LOSS) BEFORE INCOME TAXES 117,867 176,933 (498 ) (176,435 ) 117,867 INCOME TAX BENEFIT (179,331 ) — — — (179,331 ) NET INCOME (LOSS) $ 297,198 $ 176,933 $ (498 ) $ (176,435 ) $ 297,198 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Six months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Total revenues $ 360,335 $ 217,797 $ — $ — $ 578,132 Costs and expenses: Lease operating expenses 30,424 11,394 — — 41,818 Production taxes 8,804 5,709 — — 14,513 Midstream gathering and processing expenses 98,208 37,425 — — 135,633 Depreciation, depletion, and amortization 232,932 1 — — 232,933 General and administrative expenses 28,786 (1,681 ) 2 — 27,107 Accretion expense 1,585 434 — — 2,019 400,739 53,282 2 — 454,023 (LOSS) INCOME FROM OPERATIONS (40,404 ) 164,515 (2 ) — 124,109 OTHER (INCOME) EXPENSE: Interest expense 69,056 (1,387 ) — — 67,669 Interest income (58 ) (12 ) — — (70 ) Insurance proceeds (231 ) — — — (231 ) Gain on sale of equity method investments (25,616 ) (96,419 ) — — (122,035 ) (Income) loss from equity method investments and investments in subsidiaries (283,765 ) (693 ) 558 261,476 (22,424 ) Other (income) expense (1,130 ) (10 ) — 1,000 (140 ) (241,744 ) (98,521 ) 558 262,476 (77,231 ) INCOME (LOSS) BEFORE INCOME TAXES 201,340 263,036 (560 ) (262,476 ) 201,340 INCOME TAX BENEFIT (69 ) — — — (69 ) NET INCOME (LOSS) $ 201,409 $ 263,036 $ (560 ) $ (262,476 ) $ 201,409 CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Amounts in thousands) Three months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Net income (loss) $ 234,956 $ 78,291 $ (104 ) $ (78,187 ) $ 234,956 Foreign currency translation adjustment 3,610 61 3,549 (3,610 ) 3,610 Other comprehensive income (loss) 3,610 61 3,549 (3,610 ) 3,610 Comprehensive income (loss) $ 238,566 $ 78,352 $ 3,445 $ (81,797 ) $ 238,566 Three months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Net income (loss) $ 111,319 $ 176,350 $ (229 ) $ (176,121 ) $ 111,319 Foreign currency translation adjustment (3,364 ) 14 (3,378 ) 3,364 (3,364 ) Other comprehensive (loss) income (3,364 ) 14 (3,378 ) 3,364 (3,364 ) Comprehensive income (loss) $ 107,955 $ 176,364 $ (3,607 ) $ (172,757 ) $ 107,955 Six months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Net income (loss) $ 297,198 $ 176,933 $ (498 ) $ (176,435 ) $ 297,198 Foreign currency translation adjustment 7,411 155 7,256 (7,411 ) 7,411 Other comprehensive income (loss) 7,411 155 7,256 (7,411 ) 7,411 Comprehensive income (loss) $ 304,609 $ 177,088 $ 6,758 $ (183,846 ) $ 304,609 Six months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Net income (loss) $ 201,409 $ 263,036 $ (560 ) $ (262,476 ) $ 201,409 Foreign currency translation adjustment (8,867 ) (173 ) (8,694 ) 8,867 (8,867 ) Other comprehensive (loss) income (8,867 ) (173 ) (8,694 ) 8,867 (8,867 ) Comprehensive income (loss) $ 192,542 $ 262,863 $ (9,254 ) $ (253,609 ) $ 192,542 CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Amounts in thousands) Six months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Net cash provided by operating activities $ 230,776 $ 74,857 $ 3,355 $ 1 $ 308,989 Net cash (used in) provided by investing activities (324,357 ) (91,769 ) (3,751 ) 432 (419,445 ) Net cash provided by (used in) financing activities 78,936 — 433 (433 ) 78,936 Net (decrease) increase in cash, cash equivalents and restricted cash (14,645 ) (16,912 ) 37 — (31,520 ) Cash, cash equivalents and restricted cash at beginning of period 25,585 26,711 1 — 52,297 Cash, cash equivalents and restricted cash at end of period $ 10,940 $ 9,799 $ 38 $ — $ 20,777 Six months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Net cash provided by operating activities $ 370,965 $ 40,078 $ — $ 1 $ 411,044 Net cash (used in) provided by investing activities (327,362 ) (33,103 ) (1,569 ) 1,569 (360,465 ) Net cash (used in) provided by financing activities (30,906 ) — 1,570 (1,570 ) (30,906 ) Net increase in cash, cash equivalents and restricted cash 12,697 6,975 1 — 19,673 Cash, cash equivalents and restricted cash at beginning of period 67,908 31,649 — — 99,557 Cash, cash equivalents and restricted cash at end of period $ 80,605 $ 38,624 $ 1 $ — $ 119,230

RECENT ACCOUNTING PRONOUNCEMENT

RECENT ACCOUNTING PRONOUNCEMENTS	6 Months Ended
	Jun. 30, 2019
Accounting Changes and Error Corrections [Abstract]
RECENT ACCOUNTING PRONOUNCEMENTS	RECENT ACCOUNTING PRONOUNCEMENTS In February 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-02 , Leases (Topic 842) . The standard supersedes the previous lease guidance by requiring lessees to recognize a right-to-use asset and lease liability on the balance sheet for all leases with lease terms of greater than one year while maintaining substantially similar classifications for financing and operating leases. Subsequent to ASU 2016-02, the FASB issued several related ASU’s to clarify the application of the lease standard. The Company adopted the new standard as of January 1, 2019 on a prospective basis using the simplified transition method permitted by ASU 2018-11, Leases (Topic 842): Targeted Improvements. The comparative information has not been restated and continues to be reported under the historic accounting standards in effect for those periods. See Note 12 for further discussion of the lease standard. In June 2016 , the FASB issued ASU No. 2016-13 , Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments . This ASU amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities. For assets held at amortized cost basis, this ASU eliminates the probable initial recognition threshold in current GAAP and instead, requires an entity to reflect its current estimate of all expected credit losses. The amendments affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposure, reinsurance receivables and any other financial assets not excluded from the scope that have the contractual right to receive cash. Additionally, in May 2019 , the FASB issued ASU No. 2019-05 , Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief . The amendments in this update allow preparers to irrevocably elect the fair value option, on an instrument-by-instrument basis, for eligible financial assets measured at amortized cost basis upon adoption of 2016-13 . The guidance is effective for periods after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact this standard will have on its financial statements and related disclosures and does not anticipate it to have a material effect. In February 2018 , the FASB issued ASU No. 2018-02 , Income statement - Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which allows a reclassification from accumulated other comprehensive income to retained earnings for standard tax effects resulting from the Tax Cuts and Jobs Act of 2017. The amendment will be effective for reporting periods beginning after December 15, 2018 , and early adoption is permitted. The Company assessed the impact of the ASU on its consolidated financial statements and related disclosures, and determined there was no material impact. In August 2018 , the FASB issued ASU No. 2018-13 , Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement which removes, modifies, and adds certain disclosure requirements on fair value measurements. The amendment will be effective for reporting periods beginning after December 15, 2019 , and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures. In August 2018 , the FASB also issued ASU No. 2018-15 , Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract , which aligns the accounting for costs associated with implementing a cloud computing arrangement in a hosting arrangement that is a service contract with the accounting for implementation costs incurred to develop or obtain internal-use software. The amendment will be effective for reporting periods beginning after December 15, 2019 , and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures. In November 2018 , the FASB also issued ASU No. 2018-18 , Collaborative Arrangements (Topic 808): Clarifying the Interaction Between Topic 808 and Topic 606 , which provides guidance on how to assess whether certain transactions between participants in a collaborative arrangement should be accounted for within the ASU No. 2014-09 revenue recognition standard discussed above. The amendment will be effective for reporting periods beginning after December 15, 2019 , and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures.

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	6 Months Ended
	Jun. 30, 2019
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS Sale of Southern Louisiana Assets In December of 2018, the Company entered into an agreement to sell its non-core assets located in the WCBB and Hackberry fields of Louisiana to an undisclosed third party for a purchase price of approximately $19.7 million . The Company received approximately $9.2 million in cash and retained contingent overriding royalty interests. In addition, the Company could also receive contingent payments based on commodity prices exceeding certain thresholds over the next two years . The buyer has agreed to assume all plugging and abandonment liabilities associated with these assets. The effective date of the transaction is August 15, 2018. The sale closed on July 3, 2019, subject to customary post-closing terms and conditions. Debt Repurchases In July 2019, the Company used borrowings under its revolving credit facility to repurchase in the open market approximately $104.4 million aggregate principal amount of its outstanding 2023 Notes, 2024 Notes, 2025 Notes and 2026 Notes for $80.3 million

RECENT ACCOUNTING PRONOUNCEME_2

RECENT ACCOUNTING PRONOUNCEMENTS (Policies)	6 Months Ended
	Jun. 30, 2019
Accounting Changes and Error Corrections [Abstract]
Recent accounting pronouncements	In February 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-02 , Leases (Topic 842) . The standard supersedes the previous lease guidance by requiring lessees to recognize a right-to-use asset and lease liability on the balance sheet for all leases with lease terms of greater than one year while maintaining substantially similar classifications for financing and operating leases. Subsequent to ASU 2016-02, the FASB issued several related ASU’s to clarify the application of the lease standard. The Company adopted the new standard as of January 1, 2019 on a prospective basis using the simplified transition method permitted by ASU 2018-11, Leases (Topic 842): Targeted Improvements. The comparative information has not been restated and continues to be reported under the historic accounting standards in effect for those periods. See Note 12 for further discussion of the lease standard. In June 2016 , the FASB issued ASU No. 2016-13 , Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments . This ASU amends guidance on reporting credit losses for assets held at amortized cost basis and available for sale debt securities. For assets held at amortized cost basis, this ASU eliminates the probable initial recognition threshold in current GAAP and instead, requires an entity to reflect its current estimate of all expected credit losses. The amendments affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposure, reinsurance receivables and any other financial assets not excluded from the scope that have the contractual right to receive cash. Additionally, in May 2019 , the FASB issued ASU No. 2019-05 , Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief . The amendments in this update allow preparers to irrevocably elect the fair value option, on an instrument-by-instrument basis, for eligible financial assets measured at amortized cost basis upon adoption of 2016-13 . The guidance is effective for periods after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact this standard will have on its financial statements and related disclosures and does not anticipate it to have a material effect. In February 2018 , the FASB issued ASU No. 2018-02 , Income statement - Reporting Comprehensive Income (Topic 220) - Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income , which allows a reclassification from accumulated other comprehensive income to retained earnings for standard tax effects resulting from the Tax Cuts and Jobs Act of 2017. The amendment will be effective for reporting periods beginning after December 15, 2018 , and early adoption is permitted. The Company assessed the impact of the ASU on its consolidated financial statements and related disclosures, and determined there was no material impact. In August 2018 , the FASB issued ASU No. 2018-13 , Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement which removes, modifies, and adds certain disclosure requirements on fair value measurements. The amendment will be effective for reporting periods beginning after December 15, 2019 , and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures. In August 2018 , the FASB also issued ASU No. 2018-15 , Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract , which aligns the accounting for costs associated with implementing a cloud computing arrangement in a hosting arrangement that is a service contract with the accounting for implementation costs incurred to develop or obtain internal-use software. The amendment will be effective for reporting periods beginning after December 15, 2019 , and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures. In November 2018 , the FASB also issued ASU No. 2018-18 , Collaborative Arrangements (Topic 808): Clarifying the Interaction Between Topic 808 and Topic 606 , which provides guidance on how to assess whether certain transactions between participants in a collaborative arrangement should be accounted for within the ASU No. 2014-09 revenue recognition standard discussed above. The amendment will be effective for reporting periods beginning after December 15, 2019 , and early adoption is permitted. The Company is currently assessing the impact of the ASU on its consolidated financial statements and related disclosures.

PROPERTY AND EQUIPMENT (Tables)

PROPERTY AND EQUIPMENT (Tables)	6 Months Ended
	Jun. 30, 2019
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 June 30, 2019 and December 31, 2018 are as follows: June 30, 2019 December 31, 2018 (In thousands) Oil and natural gas properties $ 10,510,427 $ 10,026,836 Office furniture and fixtures 46,327 42,581 Building 44,565 44,565 Land 5,521 5,521 Total property and equipment 10,606,840 10,119,503 Accumulated depletion, depreciation, amortization and impairment (4,882,729 ) (4,640,098 ) Property and equipment, net $ 5,724,111 $ 5,479,405
Summary of non-producing properties excluded from amortization by area	The following table summarizes the Company’s non-producing properties excluded from amortization by area at June 30, 2019 : June 30, 2019 (In thousands) Utica $ 1,475,997 MidContinent 1,359,279 Niobrara 454 Southern Louisiana 611 Bakken 100 $ 2,836,441
Schedule of asset retirement obligation	A reconciliation of the Company’s asset retirement obligation for the six months ended June 30, 2019 and 2018 is as follows: June 30, 2019 June 30, 2018 (In thousands) Asset retirement obligation, beginning of period $ 79,952 $ 75,100 Liabilities incurred 5,153 909 Liabilities settled (117 ) (719 ) Accretion expense 2,426 2,019 Revisions in estimated cash flows 1,077 (374 ) Asset retirement obligation as of end of period 88,491 76,935 Less current portion — 120 Asset retirement obligation, long-term $ 88,491 $ 76,815

EQUITY INVESMENTS (Tables)

EQUITY INVESMENTS (Tables)	6 Months Ended
	Jun. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Schedule of equity method investments	Investments accounted for by the equity method consist of the following as of June 30, 2019 and December 31, 2018 : Carrying value Loss (income) from equity method investments Approximate ownership % June 30, 2019 December 31, 2018 Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (In thousands) Investment in Tatex Thailand II, LLC 23.5 % $ — $ — $ (1,945 ) $ (63 ) $ (2,085 ) $ (104 ) Investment in Grizzly Oil Sands ULC 24.9999 % 51,607 44,259 (54 ) 228 339 558 Investment in Timber Wolf Terminals LLC (1) — % — — — 534 — 536 Investment in Windsor Midstream LLC 22.5 % 39 39 — (9 ) — (9 ) Investment in Mammoth Energy Services, Inc. 21.8 % 67,661 191,823 127,581 (9,242 ) 123,055 (22,712 ) Investment in Strike Force Midstream LLC (2) — % — — — (336 ) — (693 ) $ 119,307 $ 236,121 $ 125,582 $ (8,888 ) $ 121,309 $ (22,424 ) (1) On June 5, 2018, the Company received its final distribution from Timber Wolf Terminals LLC ("Timber Wolf"). See below under Timber Wolf Terminals LLC for information regarding the subsequent dissolution of Timber Wolf. (2) On May 1, 2018, the Company sold its 25% interest in Strike Force Midstream LLC ("Strike Force") to EQT Midstream Partners, LP. See below under Strike Force Midstream LLC for information regarding this transaction.
Summary of equity investments - balance sheet	The tables below summarize financial information for the Company’s equity investments as of June 30, 2019 and December 31, 2018 . Summarized balance sheet information: June 30, 2019 December 31, 2018 (In thousands) Current assets $ 477,559 $ 471,733 Noncurrent assets $ 1,353,113 $ 1,302,488 Current liabilities $ 167,901 $ 239,975 Noncurrent liabilities $ 190,200 $ 94,575
Summary of equity investments - income statement	Summarized results of operations: Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (In thousands) Gross revenue $ 179,114 $ 566,404 $ 443,958 $ 1,067,537 Net (loss) income $ (4,072 ) $ 49,018 $ 20,684 $ 113,470

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	6 Months Ended
	Jun. 30, 2019
Long-term Debt, Unclassified [Abstract]
Summary of long-term debt	Long-term debt consisted of the following items as of June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 (In thousands) Revolving credit agreement (1) $ 155,000 $ 45,000 6.625% senior unsecured notes due 2023 350,000 350,000 6.000% senior unsecured notes due 2024 650,000 650,000 6.375% senior unsecured notes due 2025 600,000 600,000 6.375% senior unsecured notes due 2026 450,000 450,000 Net unamortized debt issuance costs (2) (28,426 ) (30,733 ) Construction loan 22,719 23,149 Less: current maturities of long term debt (615 ) (651 ) Debt reflected as long term $ 2,198,678 $ 2,086,765 (1) The Company has entered into a senior secured revolving credit facility, as amended (the "revolving credit facility"), with The Bank of Nova Scotia, as the lead arranger and administrative agent and other lenders. On June 3, 2019, the Company further amended its revolving credit facility to, among other things, allow the Company to designate certain of its subsidiaries as unrestricted subsidiaries and to include LIBOR replacement provisions. Additionally, the borrowing base was reaffirmed at $1.4 billion , and the Company’s elected commitment amount remained at $1.0 billion . As of June 30, 2019 , $155.0 million was outstanding under the revolving credit facility and the total availability for future borrowings under this facility, after giving effect to an aggregate of $251.5 million letters of credit, was $593.5 million . The Company’s wholly owned subsidiaries have guaranteed the obligations of the Company under the revolving credit facility. At June 30, 2019 , amounts borrowed under the revolving credit facility bore interest at a weighted average rate of 3.93% . The Company was in compliance with its financial covenants under the revolving credit facility at June 30, 2019 . (2) Loan issuance costs related to the 6.625% Senior Notes due 2023 (the "2023 Notes"), the 6.000% Senior Notes due 2024 (the "2024 Notes"), the 6.375% Senior Notes due 2025 (the "2025 Notes") and the 6.375% Senior Notes due 2026 (the "2026 Notes") (collectively the “Notes”) have been presented as a reduction to the Notes. At June 30, 2019 , total unamortized debt issuance costs were $4.0 million for the 2023 Notes, $8.1 million for the 2024 Notes, $11.7 million for the 2025 Notes and $4.7 million for the 2026 Notes. In addition, loan commitment fee costs for the Company's construction loan agreement were $0.1 million at June 30, 2019 .

STOCK-BASED COMPENSATION (Table

STOCK-BASED COMPENSATION (Tables)	6 Months Ended
	Jun. 30, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract]
Schedule of restricted stock activity	The following table summarizes restricted stock unit activity for the six months ended June 30, 2019 : Number of Unvested Restricted Stock Units Weighted Average Grant Date Fair Value Number of Unvested Performance Vesting Restricted Stock Units Weighted Average Grant Date Fair Value Unvested shares as of January 1, 2019 1,535,811 $ 11.57 $ — $ — Granted 770,661 6.96 228,659 9.66 Vested (325,193 ) 10.08 — — Forfeited (8,776 ) 12.44 — — Unvested shares as of June 30, 2019 1,972,503 $ 10.01 228,659 $ 9.66

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Schedule of 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 June 30, 2019 2018 Income Shares Per Share Income Shares Per Share (In thousands, except share data) Basic: Net income $ 234,956 159,324,909 $ 1.47 $ 111,319 173,623,630 $ 0.64 Effect of dilutive securities: Stock options and awards — 181,917 — 516,997 Diluted: Net income $ 234,956 159,506,826 $ 1.47 $ 111,319 174,140,627 $ 0.64 Six months ended June 30, 2019 2018 Income Shares Per Income Shares Per (In thousands, except share data) Basic: Net income $ 297,198 161,064,787 $ 1.85 $ 201,409 177,158,230 $ 1.14 Effect of dilutive securities: Stock options and awards — 525,300 — 579,052 Diluted: Net income $ 297,198 161,590,087 $ 1.84 $ 201,409 177,737,282 $ 1.13

COMMITTMENTS AND CONTINGENCIES

COMMITTMENTS AND CONTINGENCIES (Tables)	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of firm transportation commitments	The table below presents the firm sales commitments by year: (MMBtu per day) Remaining 2019 493,000 2020 276,000 2021 179,000 2022 70,000 2023 42,000 Thereafter 25,000 Total 1,085,000
Schedule of other commitments	Future minimum commitments under this agreement at June 30, 2019 are: (In thousands) Remaining 2019 $ 12,000 2020 24,000 2021 24,000 Total $ 60,000 The table below presents the firm transportation commitments by year: (In thousands) Remaining 2019 $ 122,128 2020 273,973 2021 273,011 2022 273,011 2023 268,209 Thereafter 2,283,229 Total $ 3,493,561

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	6 Months Ended
	Jun. 30, 2019
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Schedule of open fixed price swap positions and natural gas basis swap positions	Below is a summary of the Company’s open fixed price swap positions as of June 30, 2019 . Location Daily Volume (MMBtu/day) Weighted Remaining 2019 NYMEX Henry Hub 1,380,000 $ 2.81 2020 NYMEX Henry Hub 204,000 $ 2.77 Location Daily Volume Weighted Remaining 2019 NYMEX WTI 6,000 $ 60.81 2020 NYMEX WTI 6,000 $ 59.82 Location Daily Volume Weighted Remaining 2019 Mont Belvieu C2 1,000 $ 18.48 Remaining 2019 Mont Belvieu C3 4,000 $ 29.02 Remaining 2019 Mont Belvieu C5 1,000 $ 53.71 The Company sold call options and used the associated premiums to enhance the fixed price for a portion of the fixed price natural gas swaps listed above. Each short call option has an established ceiling price. When the referenced settlement price is above the price ceiling established by these short call options, the Company pays its counterparty an amount equal to the difference between the referenced settlement price and the price ceiling multiplied by the hedged contract volumes. Location Daily Volume (MMBtu/day) Weighted Average Price Remaining 2019 NYMEX Henry Hub 30,000 $ 3.10 June 30, 2019 , the Company had the following natural gas basis swap positions open: Gulfport Pays Gulfport Receives Daily Volume (MMBtu/day) Weighted Average Fixed Spread Remaining 2019 Transco Zone 4 NYMEX Plus Fixed Spread 60,000 $ (0.05 ) 2020 Transco Zone 4 NYMEX Plus Fixed Spread 60,000 $ (0.05 ) 2020 Fixed Spread ONEOK Minus NYMEX 10,000 $ (0.54 )
Schedule of derivative instruments in balance sheet	The following table presents the fair value of the Company’s derivative instruments on a gross basis at June 30, 2019 and December 31, 2018 : June 30, 2019 December 31, 2018 (In thousands) Short-term derivative instruments - asset $ 134,920 $ 21,352 Long-term derivative instruments - asset $ 5,036 $ — Short-term derivative instruments - liability $ 198 $ 20,401 Long-term derivative instruments - liability $ 210 $ 13,992
Schedule of net gain (loss) on derivatives	The following table presents the gain and loss recognized in net gain (loss) on natural gas, oil and NGL derivatives in the accompanying consolidated statements of operations for the three and six months ended June 30, 2019 and 2018 . Net gain (loss) on derivative instruments Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (In thousands) Natural gas derivatives $ 152,475 $ (31,194 ) $ 136,044 $ (40,890 ) Oil derivatives 11,871 (24,419 ) 11,417 (33,566 ) NGL derivatives 6,794 (14,932 ) 3,634 (12,618 ) Total $ 171,140 $ (70,545 ) $ 151,095 $ (87,074 )
Recognized derivative assets	The following table presents the gross amounts of recognized derivative assets and liabilities in the consolidated balance sheets and the amounts that are subject to offsetting under master netting arrangements with counterparties, all at fair value. As of June 30, 2019 Gross Assets (Liabilities) Gross Amounts Presented in the Subject to Master Net Consolidated Balance Sheets Netting Agreements Amount (In thousands) Derivative assets $ 139,956 $ (408 ) $ 139,548 Derivative liabilities $ (408 ) $ 408 $ — As of December 31, 2018 Gross Assets (Liabilities) Gross Amounts Presented in the Subject to Master Net Consolidated Balance Sheets Netting Agreements Amount (In thousands) Derivative assets $ 21,352 $ (19,289 ) $ 2,063 Derivative liabilities $ (34,393 ) $ 19,289 $ (15,104 )
Recognized derivative liabilities	The following table presents the gross amounts of recognized derivative assets and liabilities in the consolidated balance sheets and the amounts that are subject to offsetting under master netting arrangements with counterparties, all at fair value. As of June 30, 2019 Gross Assets (Liabilities) Gross Amounts Presented in the Subject to Master Net Consolidated Balance Sheets Netting Agreements Amount (In thousands) Derivative assets $ 139,956 $ (408 ) $ 139,548 Derivative liabilities $ (408 ) $ 408 $ — As of December 31, 2018 Gross Assets (Liabilities) Gross Amounts Presented in the Subject to Master Net Consolidated Balance Sheets Netting Agreements Amount (In thousands) Derivative assets $ 21,352 $ (19,289 ) $ 2,063 Derivative liabilities $ (34,393 ) $ 19,289 $ (15,104 )

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Summary of financial and non-financial assets and liabilities by valuation level	The following tables summarize the Company’s financial and non-financial assets and liabilities by valuation level as of June 30, 2019 and December 31, 2018 : June 30, 2019 Level 1 Level 2 Level 3 (In thousands) Assets: Derivative Instruments $ — $ 139,956 $ — Liabilities: Derivative Instruments $ — $ 408 $ — December 31, 2018 Level 1 Level 2 Level 3 (In thousands) Assets: Derivative Instruments $ — $ 21,352 $ — Liabilities: Derivative Instruments $ — $ 34,393 $ —

LEASES (Tables)

LEASES (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Schedule of operating lease liability	Maturities of operating lease liabilities as of June 30, 2019 were as follows: (In thousands) Remaining 2019 $ 25,243 2020 27,481 2021 22,731 2022 115 2023 90 Thereafter 30 Total lease payments $ 75,690 Less: Imputed interest (2,777 ) Total $ 72,913
Schedule of lease cost	Lease cost for the six months ended June 30, 2019 consisted of the following: (In thousands) Operating lease cost $ 16,284 Operating lease cost - related party 11,220 Variable lease cost 960 Variable lease cost - related party 59,611 Short-term lease cost 183 Total lease cost (1) $ 88,258 (1) The majority of the Company's total lease cost was capitalized to the full cost pool, and the remainder was included in general and administrative expenses in the accompanying consolidated statement of operations. Supplemental cash flow information for the six months ended June 30, 2019 related to leases was as follows: Cash paid for amounts included in the measurement of lease liabilities (In thousands) Operating cash flows from operating leases $ 120 Investing cash flow from operating leases $ 12,288 Investing cash flow from operating leases - related party $ 43,925

CONDENSED CONSOLIDATING FINAN_2

CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Tables)	6 Months Ended
	Jun. 30, 2019
Condensed Financial Information Disclosure [Abstract]
CONDENSED CONSOLIDATING BALANCE SHEETS	CONDENSED CONSOLIDATING BALANCE SHEETS (Amounts in thousands) June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 10,940 $ 9,799 $ 38 $ — $ 20,777 Accounts receivable - oil and natural gas sales 4,116 127,559 — — 131,675 Accounts receivable - joint interest and other 9,043 37,602 — — 46,645 Accounts receivable - intercompany 819,584 433,776 — (1,253,360 ) — Prepaid expenses and other current assets 5,948 3,451 75 — 9,474 Short-term derivative instruments 134,920 — — — 134,920 Total current assets 984,551 612,187 113 (1,253,360 ) 343,491 Property and equipment: Oil and natural gas properties, full-cost accounting 1,352,894 9,158,193 69 (729 ) 10,510,427 Other property and equipment 92,343 751 3,319 — 96,413 Accumulated depletion, depreciation, amortization and impairment (1,414,011 ) (3,468,663 ) (55 ) — (4,882,729 ) Property and equipment, net 31,226 5,690,281 3,333 (729 ) 5,724,111 Other assets: Equity investments and investments in subsidiaries 5,171,925 — 51,607 (5,104,225 ) 119,307 Long-term derivative instruments 5,036 — — — 5,036 Deferred tax asset 179,331 — — — 179,331 Inventories 188 8,813 — — 9,001 Operating lease assets 19,334 — — — 19,334 Operating lease assets - related parties 53,579 — — — 53,579 Other assets 11,682 598 — — 12,280 Total other assets 5,441,075 9,411 51,607 (5,104,225 ) 397,868 Total assets $ 6,456,852 $ 6,311,879 $ 55,053 $ (6,358,314 ) $ 6,465,470 Liabilities and Stockholders ’ Equity Current liabilities: Accounts payable and accrued liabilities $ 74,597 $ 419,190 $ 43 $ — $ 493,830 Accounts payable - intercompany 469,071 780,600 3,689 (1,253,360 ) — Short-term derivative instruments 198 — — — 198 Current portion of operating lease liabilities 17,999 — — — 17,999 Current portion of operating lease liabilities - related parties 20,817 — — — 20,817 Current maturities of long-term debt 615 — — — 615 Total current liabilities 583,297 1,199,790 3,732 (1,253,360 ) 533,459 Long-term derivative instruments 210 — — — 210 Asset retirement obligation - long-term 30,035 58,456 — — 88,491 Deferred tax liability 3,127 — — — 3,127 Non-current operating lease liabilities 1,335 — — — 1,335 Non-current operating lease liabilities - related parties 32,762 — — — 32,762 Long-term debt, net of current maturities 2,198,678 — — — 2,198,678 Total liabilities 2,849,444 1,258,246 3,732 (1,253,360 ) 2,858,062 Stockholders’ equity: Common stock 1,594 — — — 1,594 Paid-in capital 4,202,599 4,170,574 262,059 (4,432,633 ) 4,202,599 Accumulated other comprehensive loss (48,615 ) — (46,527 ) 46,527 (48,615 ) (Accumulated deficit) retained earnings (548,170 ) 883,059 (164,211 ) (718,848 ) (548,170 ) Total stockholders’ equity 3,607,408 5,053,633 51,321 (5,104,954 ) 3,607,408 Total liabilities and stockholders ’ equity $ 6,456,852 $ 6,311,879 $ 55,053 $ (6,358,314 ) $ 6,465,470 CONDENSED CONSOLIDATING BALANCE SHEETS (Amounts in thousands) December 31, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 25,585 $ 26,711 $ 1 $ — $ 52,297 Accounts receivable - oil and natural gas sales 146,075 64,125 — — 210,200 Accounts receivable - joint interest and other 16,212 6,285 — — 22,497 Accounts receivable - intercompany 671,633 319,464 — (991,097 ) — Prepaid expenses and other current assets 8,433 2,174 — — 10,607 Short-term derivative instruments 21,352 — — — 21,352 Total current assets 889,290 418,759 1 (991,097 ) 316,953 Property and equipment: Oil and natural gas properties, full-cost accounting, 7,044,550 2,983,015 — (729 ) 10,026,836 Other property and equipment 91,916 751 — — 92,667 Accumulated depletion, depreciation, amortization and impairment (4,640,059 ) (39 ) — — (4,640,098 ) Property and equipment, net 2,496,407 2,983,727 — (729 ) 5,479,405 Other assets: Equity investments and investments in subsidiaries 2,856,988 — 44,259 (2,665,126 ) 236,121 Inventories 3,620 1,134 — — 4,754 Other assets 12,624 1,178 — 1 13,803 Total other assets 2,873,232 2,312 44,259 (2,665,125 ) 254,678 Total assets $ 6,258,929 $ 3,404,798 $ 44,260 $ (3,656,951 ) $ 6,051,036 Liabilities and Stockholders ’ Equity Current liabilities: Accounts payable and accrued liabilities $ 419,107 $ 99,273 $ — $ — $ 518,380 Accounts payable - intercompany 320,259 670,708 130 (991,097 ) — Short-term derivative instruments 20,401 — — — 20,401 Current maturities of long-term debt 651 — — — 651 Total current liabilities 760,418 769,981 130 (991,097 ) 539,432 Long-term derivative instruments 13,992 — — — 13,992 Asset retirement obligation - long-term 66,859 13,093 — — 79,952 Deferred tax liability 3,127 — — — 3,127 Long-term debt, net of current maturities 2,086,765 — — — 2,086,765 Total liabilities 2,931,161 783,074 130 (991,097 ) 2,723,268 Stockholders’ equity: Common stock 1,630 — — — 1,630 Paid-in capital 4,227,532 1,915,598 261,626 (2,177,224 ) 4,227,532 Accumulated other comprehensive loss (56,026 ) — (53,783 ) 53,783 (56,026 ) (Accumulated deficit) retained earnings (845,368 ) 706,126 (163,713 ) (542,413 ) (845,368 ) Total stockholders’ equity 3,327,768 2,621,724 44,130 (2,665,854 ) 3,327,768 Total liabilities and stockholders ’ equity $ 6,258,929 $ 3,404,798 $ 44,260 $ (3,656,951 ) $ 6,051,036
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS	CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Three months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Total revenues $ 280,291 $ 178,703 $ — $ — $ 458,994 Costs and expenses: Lease operating expenses 12,256 10,132 — — 22,388 Production taxes 2,820 5,278 — — 8,098 Midstream gathering and processing expenses 28,121 43,894 — — 72,015 Depreciation, depletion and amortization 80,132 44,764 55 — 124,951 General and administrative expenses 16,745 (3,583 ) 103 — 13,265 Accretion expense 438 921 — — 1,359 140,512 101,406 158 — 242,076 INCOME (LOSS) FROM OPERATIONS 139,779 77,297 (158 ) — 216,918 OTHER EXPENSE (INCOME): Interest expense 35,835 (955 ) — — 34,880 Interest income (120 ) (39 ) — — (159 ) Insurance proceeds (83 ) — — — (83 ) Loss (income) from equity method investments and investments in subsidiaries 47,449 — (54 ) 78,187 125,582 Other expense 1,073 — — — 1,073 84,154 (994 ) (54 ) 78,187 161,293 INCOME (LOSS) BEFORE INCOME TAXES 55,625 78,291 (104 ) (78,187 ) 55,625 INCOME TAX BENEFIT (179,331 ) — — — (179,331 ) NET INCOME (LOSS) $ 234,956 $ 78,291 $ (104 ) $ (78,187 ) $ 234,956 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Three months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Total revenues $ 146,774 $ 105,966 $ — $ — $ 252,740 Costs and expenses: Lease operating expenses 16,593 6,319 — — 22,912 Production taxes 4,793 2,866 — — 7,659 Midstream gathering and processing expenses 52,542 18,898 — — 71,440 Depreciation, depletion and amortization 121,915 — — — 121,915 General and administrative expenses 14,975 (968 ) 1 — 14,008 Accretion expense 795 220 — — 1,015 211,613 27,335 1 — 238,949 (LOSS) INCOME FROM OPERATIONS (64,839 ) 78,631 (1 ) — 13,791 OTHER (INCOME) EXPENSE: Interest expense 34,663 (959 ) — — 33,704 Interest income (27 ) (6 ) — — (33 ) Insurance proceeds (231 ) — — — (231 ) Gain on sale of equity method investments (25,616 ) (96,419 ) — — (122,035 ) (Income) loss from equity method investments and investments in subsidiaries (183,901 ) (336 ) 228 175,121 (8,888 ) Other (income) expense (1,046 ) 1 — 1,000 (45 ) (176,158 ) (97,719 ) 228 176,121 (97,528 ) INCOME (LOSS) BEFORE INCOME TAXES 111,319 176,350 (229 ) (176,121 ) 111,319 INCOME TAX BENEFIT — — — — — NET INCOME (LOSS) $ 111,319 $ 176,350 $ (229 ) $ (176,121 ) $ 111,319 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Six months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Total revenues $ 466,537 $ 313,035 $ — $ — $ 779,572 Costs and expenses: Lease operating expenses 27,149 15,046 — — 42,195 Production taxes 6,081 9,938 — — 16,019 Midstream gathering and processing expenses 71,420 70,877 — — 142,297 Depreciation, depletion, and amortization 198,564 44,765 55 — 243,384 General and administrative expenses 28,977 (4,258 ) 104 — 24,823 Accretion expense 1,389 1,037 — — 2,426 333,580 137,405 159 — 471,144 INCOME (LOSS) FROM OPERATIONS 132,957 175,630 (159 ) — 308,428 OTHER EXPENSE (INCOME): Interest expense 70,259 (1,259 ) — — 69,000 Interest income (267 ) (44 ) — — (311 ) Insurance proceeds (83 ) — — — (83 ) (Income) loss from equity method investments and investments in subsidiaries (55,465 ) — 339 176,435 121,309 Other expense 646 — — — 646 15,090 (1,303 ) 339 176,435 190,561 INCOME (LOSS) BEFORE INCOME TAXES 117,867 176,933 (498 ) (176,435 ) 117,867 INCOME TAX BENEFIT (179,331 ) — — — (179,331 ) NET INCOME (LOSS) $ 297,198 $ 176,933 $ (498 ) $ (176,435 ) $ 297,198 CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Amounts in thousands) Six months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Total revenues $ 360,335 $ 217,797 $ — $ — $ 578,132 Costs and expenses: Lease operating expenses 30,424 11,394 — — 41,818 Production taxes 8,804 5,709 — — 14,513 Midstream gathering and processing expenses 98,208 37,425 — — 135,633 Depreciation, depletion, and amortization 232,932 1 — — 232,933 General and administrative expenses 28,786 (1,681 ) 2 — 27,107 Accretion expense 1,585 434 — — 2,019 400,739 53,282 2 — 454,023 (LOSS) INCOME FROM OPERATIONS (40,404 ) 164,515 (2 ) — 124,109 OTHER (INCOME) EXPENSE: Interest expense 69,056 (1,387 ) — — 67,669 Interest income (58 ) (12 ) — — (70 ) Insurance proceeds (231 ) — — — (231 ) Gain on sale of equity method investments (25,616 ) (96,419 ) — — (122,035 ) (Income) loss from equity method investments and investments in subsidiaries (283,765 ) (693 ) 558 261,476 (22,424 ) Other (income) expense (1,130 ) (10 ) — 1,000 (140 ) (241,744 ) (98,521 ) 558 262,476 (77,231 ) INCOME (LOSS) BEFORE INCOME TAXES 201,340 263,036 (560 ) (262,476 ) 201,340 INCOME TAX BENEFIT (69 ) — — — (69 ) NET INCOME (LOSS) $ 201,409 $ 263,036 $ (560 ) $ (262,476 ) $ 201,409
CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS)	CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Amounts in thousands) Three months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Net income (loss) $ 234,956 $ 78,291 $ (104 ) $ (78,187 ) $ 234,956 Foreign currency translation adjustment 3,610 61 3,549 (3,610 ) 3,610 Other comprehensive income (loss) 3,610 61 3,549 (3,610 ) 3,610 Comprehensive income (loss) $ 238,566 $ 78,352 $ 3,445 $ (81,797 ) $ 238,566 Three months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Net income (loss) $ 111,319 $ 176,350 $ (229 ) $ (176,121 ) $ 111,319 Foreign currency translation adjustment (3,364 ) 14 (3,378 ) 3,364 (3,364 ) Other comprehensive (loss) income (3,364 ) 14 (3,378 ) 3,364 (3,364 ) Comprehensive income (loss) $ 107,955 $ 176,364 $ (3,607 ) $ (172,757 ) $ 107,955 Six months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Net income (loss) $ 297,198 $ 176,933 $ (498 ) $ (176,435 ) $ 297,198 Foreign currency translation adjustment 7,411 155 7,256 (7,411 ) 7,411 Other comprehensive income (loss) 7,411 155 7,256 (7,411 ) 7,411 Comprehensive income (loss) $ 304,609 $ 177,088 $ 6,758 $ (183,846 ) $ 304,609 Six months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Net income (loss) $ 201,409 $ 263,036 $ (560 ) $ (262,476 ) $ 201,409 Foreign currency translation adjustment (8,867 ) (173 ) (8,694 ) 8,867 (8,867 ) Other comprehensive (loss) income (8,867 ) (173 ) (8,694 ) 8,867 (8,867 ) Comprehensive income (loss) $ 192,542 $ 262,863 $ (9,254 ) $ (253,609 ) $ 192,542
CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS	CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Amounts in thousands) Six months ended June 30, 2019 Parent Guarantors Non-Guarantors Eliminations Consolidated Net cash provided by operating activities $ 230,776 $ 74,857 $ 3,355 $ 1 $ 308,989 Net cash (used in) provided by investing activities (324,357 ) (91,769 ) (3,751 ) 432 (419,445 ) Net cash provided by (used in) financing activities 78,936 — 433 (433 ) 78,936 Net (decrease) increase in cash, cash equivalents and restricted cash (14,645 ) (16,912 ) 37 — (31,520 ) Cash, cash equivalents and restricted cash at beginning of period 25,585 26,711 1 — 52,297 Cash, cash equivalents and restricted cash at end of period $ 10,940 $ 9,799 $ 38 $ — $ 20,777 Six months ended June 30, 2018 Parent Guarantors Non-Guarantor Eliminations Consolidated Net cash provided by operating activities $ 370,965 $ 40,078 $ — $ 1 $ 411,044 Net cash (used in) provided by investing activities (327,362 ) (33,103 ) (1,569 ) 1,569 (360,465 ) Net cash (used in) provided by financing activities (30,906 ) — 1,570 (1,570 ) (30,906 ) Net increase in cash, cash equivalents and restricted cash 12,697 6,975 1 — 19,673 Cash, cash equivalents and restricted cash at beginning of period 67,908 31,649 — — 99,557 Cash, cash equivalents and restricted cash at end of period $ 80,605 $ 38,624 $ 1 $ — $ 119,230

PROPERTY AND EQUIPMENT (Schedul

PROPERTY AND EQUIPMENT (Schedule of Property and Equipment) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Oil and natural gas properties	$ 10,510,427	$ 10,026,836
Office furniture and fixtures	46,327	42,581
Building	44,565	44,565
Land	5,521	5,521
Total property and equipment	10,606,840	10,119,503
Accumulated depletion, depreciation, amortization and impairment	(4,882,729)	(4,640,098)
Property and equipment, net	$ 5,724,111	$ 5,479,405

PROPERTY AND EQUIPMENT (Narrati

PROPERTY AND EQUIPMENT (Narrative) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)usd_per_mcf	Jun. 30, 2018USD ($)usd_per_mcf	Dec. 31, 2018USD ($)
Property, Plant and Equipment [Line Items]
Impairment of oil and gas properties	$ 0	$ 0	$ 0	$ 0
Cumulative capitalization of general and administrative costs incurred and capitalized to the full cost pool	219,800,000		219,800,000
Capitalized general and administrative costs	8,800,000	$ 9,400,000	$ 16,500,000	$ 18,200,000
Depletion per Mcfe of gas equivalent (usd per Mcfe) | usd_per_mcf			1	0.96
Capitalized costs of oil and natural gas properties excluded from amortization	$ 2,836,441,000		$ 2,836,441,000		$ 2,873,037,000
Non-producing leases, extension term	5 years		5 years
Minimum
Property, Plant and Equipment [Line Items]
Expected number of years amortization will commence			3 years
Maximum
Property, Plant and Equipment [Line Items]
Expected number of years amortization will commence			5 years

PROPERTY AND EQUIPMENT (Summary

PROPERTY AND EQUIPMENT (Summary of Non-producing Properties Excluded from Amortization by Area) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total non-producing properties not subject to amortization	$ 2,836,441	$ 2,873,037
Utica
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total non-producing properties not subject to amortization	1,475,997
MidContinent
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total non-producing properties not subject to amortization	1,359,279
Niobrara
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total non-producing properties not subject to amortization	454
Southern Louisiana
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total non-producing properties not subject to amortization	611
Bakken
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Total non-producing properties not subject to amortization	$ 100

PROPERTY AND EQUIPMENT (Sched_2

PROPERTY AND EQUIPMENT (Schedule of Asset Retirement Obligation) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation, beginning of period			$ 79,952	$ 75,100
Liabilities incurred			5,153	909
Liabilities settled			(117)	(719)
Accretion expense	$ 1,359	$ 1,015	2,426	2,019
Revisions in estimated cash flows			1,077	(374)
Asset retirement obligation as of end of period	88,491	76,935	88,491	76,935
Less current portion	0	120	0	120
Asset retirement obligation, long-term	$ 88,491	$ 76,815	$ 88,491	$ 76,815	$ 79,952

EQUITY INVESMENTS (Investments

EQUITY INVESMENTS (Investments Accounted for by the Equity Method) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	May 01, 2018
Schedule of Equity Method Investments [Line Items]
Equity investments and investments in subsidiaries	$ 119,307		$ 119,307		$ 236,121
Loss (income) from equity method investments, net	$ 125,582	$ (8,888)	$ 121,309	$ (22,424)
Investment in Tatex Thailand II, LLC
Schedule of Equity Method Investments [Line Items]
Approximate ownership %	23.50%		23.50%
Equity investments and investments in subsidiaries	$ 0		$ 0		0
Loss (income) from equity method investments, net	$ (1,945)	(63)	$ (2,085)	(104)
Investment in Grizzly Oil Sands ULC
Schedule of Equity Method Investments [Line Items]
Approximate ownership %	24.9999%		24.9999%
Equity investments and investments in subsidiaries	$ 51,607		$ 51,607		44,259
Loss (income) from equity method investments, net	$ (54)	228	$ 339	558
Investment in Timber Wolf Terminals LLC(1)
Schedule of Equity Method Investments [Line Items]
Approximate ownership %	0.00%		0.00%
Equity investments and investments in subsidiaries	$ 0		$ 0		0
Loss (income) from equity method investments, net	$ 0	534	$ 0	536
Investment in Windsor Midstream LLC
Schedule of Equity Method Investments [Line Items]
Approximate ownership %	22.50%		22.50%
Equity investments and investments in subsidiaries	$ 39		$ 39		39
Loss (income) from equity method investments, net	0	(9)	0	(9)
Investment in Mammoth Energy Services, Inc.
Schedule of Equity Method Investments [Line Items]
Equity investments and investments in subsidiaries	67,661		67,661		191,823
Loss (income) from equity method investments, net	$ 127,581	(9,242)	$ 123,055	(22,712)
Investment in Strike Force Midstream LLC
Schedule of Equity Method Investments [Line Items]
Approximate ownership %	0.00%		0.00%			25.00%
Equity investments and investments in subsidiaries	$ 0		$ 0		$ 0
Loss (income) from equity method investments, net	$ 0	$ (336)	$ 0	$ (693)

EQUITY INVESMENTS (Equity Inves

EQUITY INVESMENTS (Equity Investments Balance Sheet Disclosure) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Current assets	$ 477,559	$ 471,733
Noncurrent assets	1,353,113	1,302,488
Current liabilities	167,901	239,975
Noncurrent liabilities	$ 190,200	$ 94,575

EQUITY INVESMENTS (Equity Inv_2

EQUITY INVESMENTS (Equity Investment Income Statement Disclosure) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Gross revenue	$ 179,114	$ 566,404	$ 443,958	$ 1,067,537
Net (loss) income	$ (4,072)	$ 49,018	$ 20,684	$ 113,470

EQUITY INVESMENTS (Narrative) (

EQUITY INVESMENTS (Narrative) (Details) $ / shares in Units, a in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)shares	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)a$ / sharesshares	Jun. 30, 2018USD ($)	May 31, 2018	May 01, 2018
Schedule of Equity Method Investments [Line Items]
Loss (income) from equity method investments, net	$ 125,582,000	$ (8,888,000)	$ 121,309,000	$ (22,424,000)
Distributions from equity method investments			1,945,000	1,196,000
Mammoth Energy Services LP
Schedule of Equity Method Investments [Line Items]
Equity method investment, impairment			125,400,000
Distributions from equity method investments			$ 2,500,000
Equity method investment, ownership interest (in shares) | shares	9,829,548		9,829,548
Share dividend (in usd per share) | $ / shares			$ 0.125
Approximate fair value, quoted market price	$ 67,700,000		$ 67,700,000
Tatex Thailand II, LLC
Schedule of Equity Method Investments [Line Items]
Loss (income) from equity method investments, net	$ (1,945,000)	(63,000)	$ (2,085,000)	(104,000)
Equity method investment, ownership interest, percent	23.50%		23.50%
Grizzly Oil Sands ULC
Schedule of Equity Method Investments [Line Items]
Gas and oil area, reserve (in acres) | a			830
Loss (income) from equity method investments, net	$ (54,000)	228,000	$ 339,000	558,000
Equity method investment, impairment			0	0
Equity method investment, amount of cash calls, based on proportionate ownership interest			400,000
Equity method investments, increase (decrease) due to foreign currency translation adjustment	$ 3,500,000	(3,400,000)	$ 7,300,000	(8,700,000)
Equity method investment, ownership interest, percent	24.9999%		24.9999%
Windsor Midstream LLC
Schedule of Equity Method Investments [Line Items]
Loss (income) from equity method investments, net	$ 0	(9,000)	$ 0	(9,000)
Equity method investment, ownership interest, percent	22.50%		22.50%
Distributions from equity method investments			$ 0
Mammoth Energy Services LP
Schedule of Equity Method Investments [Line Items]
Equity method investments, increase (decrease) due to foreign currency translation adjustment	$ 100,000	(100,000)	200,000	(300,000)
Strike Force Midstream LLC
Schedule of Equity Method Investments [Line Items]
Loss (income) from equity method investments, net	$ 0	$ (336,000)	$ 0	$ (693,000)
Equity method investment, ownership interest, percent	0.00%		0.00%			25.00%
Phu Horm Field | Apico Llc
Schedule of Equity Method Investments [Line Items]
Gas and oil area, reserve (in acres) | a			108
Apico Llc | Tatex Thailand II, LLC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	8.50%		8.50%
Apico Llc | Tatex Thailand II, LLC
Schedule of Equity Method Investments [Line Items]
Loss (income) from equity method investments, net			$ (1,900,000)
Investee | Mammoth Energy Services LP
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership interest, percent	21.80%		21.80%
Investee | Strike Force Midstream LLC
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership interest, percent					25.00%

LONG-TERM DEBT (Break-Down of L

LONG-TERM DEBT (Break-Down of Long-Term Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Net unamortized debt issuance costs	$ (28,426)	$ (30,733)
Less: current maturities of long term debt	(615)	(651)
Long-term debt, net of current maturities	2,198,678	2,086,765
Construction loan
Debt Instrument [Line Items]
Net unamortized debt issuance costs	(100)
6.625% senior unsecured notes due 2023 | Senior notes
Debt Instrument [Line Items]
Long-term debt	350,000	350,000
Net unamortized debt issuance costs	$ (4,000)
Stated interest rate, percent	6.625%
6.000% senior unsecured notes due 2024 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 650,000	650,000
Net unamortized debt issuance costs	$ (8,100)
Stated interest rate, percent	6.00%
6.375% senior unsecured notes due 2025 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 600,000	600,000
Net unamortized debt issuance costs	$ (11,700)
Stated interest rate, percent	6.375%
6.375% senior unsecured notes due 2026 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 450,000	450,000
Net unamortized debt issuance costs	$ (4,700)
Stated interest rate, percent	6.375%
Nova Scotia, Amegy, KeyBank | Revolving credit agreement | Revolving credit agreement
Debt Instrument [Line Items]
Long-term debt	$ 155,000	45,000
InterBank | Letter of credit | Construction loan
Debt Instrument [Line Items]
Long-term debt	$ 22,719	$ 23,149

LONG-TERM DEBT (Narrative) (Det

LONG-TERM DEBT (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 03, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Capitalized interest expense, undeveloped properties	$ 1,000,000	$ 1,500,000	$ 1,800,000	$ 2,400,000
Debt issuance costs, net	28,426,000		28,426,000			$ 30,733,000
Construction loan
Debt Instrument [Line Items]
Debt issuance costs, net	100,000		100,000
6.000% senior unsecured notes due 2024 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 650,000,000		$ 650,000,000			650,000,000
Stated interest rate, percent	6.00%		6.00%
Debt issuance costs, net	$ 8,100,000		$ 8,100,000
6.625% senior unsecured notes due 2023 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 350,000,000		$ 350,000,000			350,000,000
Stated interest rate, percent	6.625%		6.625%
Debt issuance costs, net	$ 4,000,000		$ 4,000,000
6.375% senior unsecured notes due 2025 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 600,000,000		$ 600,000,000			600,000,000
Stated interest rate, percent	6.375%		6.375%
Debt issuance costs, net	$ 11,700,000		$ 11,700,000
6.375% senior unsecured notes due 2026 | Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 450,000,000		$ 450,000,000			450,000,000
Stated interest rate, percent	6.375%		6.375%
Debt issuance costs, net	$ 4,700,000		$ 4,700,000
Nova Scotia, Amegy, KeyBank | Revolving credit agreement
Debt Instrument [Line Items]
Credit facility interest rate at the eurodollar rate			3.93%
Nova Scotia, Amegy, KeyBank | Revolving credit agreement | Revolving credit agreement
Debt Instrument [Line Items]
Borrowing base					$ 1,400,000,000
Elected commitment amount					$ 1,000,000,000
Long-term debt	155,000,000		$ 155,000,000			$ 45,000,000
Remaining borrowing capacity	593,500,000		593,500,000
Nova Scotia, Amegy, KeyBank | Letter of credit | Revolving credit agreement
Debt Instrument [Line Items]
Credit facility outstanding	$ 251,500,000		$ 251,500,000

COMMON STOCK AND CHANGES IN C_2

COMMON STOCK AND CHANGES IN CAPITALIZATION (Details) - USD ($)	1 Months Ended	3 Months Ended				6 Months Ended	12 Months Ended
	Jan. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Dec. 31, 2018	May 31, 2018	Jan. 31, 2018
Class of Stock [Line Items]
Stock repurchase program, amount authorized to acquire	$ 400,000,000								$ 100,000,000
Value of shares repurchased during the period							$ 200,000,000
Stock repurchase program, period in force	24 months
Value of shares repurchased		$ 2,270,000	$ 28,330,000	$ 5,000,000	$ 99,997,000
Share purchased to satisfy tax withholding requirements (in shares)		100,000				100,000
Shares repurchased to satisfy tax withholding requirements		$ 500,000				$ 600,000
Common Stock
Class of Stock [Line Items]
Shares repurchased (in shares)		296,587	3,618,634	412,516	9,692,356
Value of shares repurchased		$ 3,000	$ 37,000	$ 4,000	$ 97,000
Minimum
Class of Stock [Line Items]
Stock repurchase program, amount authorized to acquire								$ 100,000,000
Maximum
Class of Stock [Line Items]
Stock repurchase program, amount authorized to acquire								$ 200,000,000
Share Repurchase Program
Class of Stock [Line Items]
Shares repurchased (in shares)							20,700,000
Share Repurchase Program | Common Stock
Class of Stock [Line Items]
Shares repurchased (in shares)		200,000				3,800,000
Value of shares repurchased		$ 1,800,000				$ 30,000,000

STOCK-BASED COMPENSATION (Narra

STOCK-BASED COMPENSATION (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation cost	$ 2.8	$ 3.3	$ 5.6	$ 6
Capitalized stock-based compensation cost	1.1	$ 1.3	2.3	$ 2.4
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	13.8		$ 13.8
Weighted average period of expense recognition period			1 year 10 months 24 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 1.9		$ 1.9
Weighted average period of expense recognition period			2 years 6 months 3 days
Performance period			36 months
Expected performance period			3 years
Risk-free interest rate			2.42%
Range of expected volatility, minimum			30.50%
Range of expected volatility, maximum			72.60%
Minimum | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Maximum | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years

STOCK-BASED COMPENSATION (Restr

STOCK-BASED COMPENSATION (Restricted Stock Award and Unit Activity) (Details)	6 Months Ended
	Jun. 30, 2019$ / sharesshares
Restricted Stock
Number of Unvested Restricted Shares
Unvested shares, beginning balance (in shares) | shares	1,535,811
Granted (in shares) | shares	770,661
Vested (in shares) | shares	(325,193)
Forfeited (in shares) | shares	(8,776)
Unvested shares, ending balance (in shares) | shares	1,972,503
Weighted Average Grant Date Fair Value
Unvested shares, beginning balance (in dollars per share) | $ / shares	$ 11.57
Granted (in dollars per share) | $ / shares	6.96
Vested (in dollars per share) | $ / shares	10.08
Forfeited (in dollars per share) | $ / shares	12.44
Unvested shares, ending balance (in dollars per share) | $ / shares	$ 10.01
Performance Shares
Number of Unvested Restricted Shares
Unvested shares, beginning balance (in shares) | shares	0
Granted (in shares) | shares	228,659
Vested (in shares) | shares	0
Forfeited (in shares) | shares	0
Unvested shares, ending balance (in shares) | shares	228,659
Weighted Average Grant Date Fair Value
Unvested shares, beginning balance (in dollars per share) | $ / shares	$ 0
Granted (in dollars per share) | $ / shares	9.66
Vested (in dollars per share) | $ / shares	0
Forfeited (in dollars per share) | $ / shares	0
Unvested shares, ending balance (in dollars per share) | $ / shares	$ 9.66

EARNINGS PER SHARE (Details)

EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Basic:
Net income - basic	$ 234,956	$ 111,319	$ 297,198	$ 201,409
Net income - basic (in shares)	159,324,909	173,623,630	161,064,787	177,158,230
Net income - basic (in usd per share)	$ 1.47	$ 0.64	$ 1.85	$ 1.14
Effect of dilutive securities:
Stock options and awards	$ 0	$ 0	$ 0	$ 0
Stock options and awards (in shares)	181,917	516,997	525,300	579,052
Diluted:
Net income - diluted	$ 234,956	$ 111,319	$ 297,198	$ 201,409
Net income - diluted (in shares)	159,506,826	174,140,627	161,590,087	177,737,282
Net income - diluted (in usd per share)	$ 1.47	$ 0.64	$ 1.84	$ 1.13

COMMITTMENTS AND CONTINGENCIE_2

COMMITTMENTS AND CONTINGENCIES (Narrative) (Details)	Apr. 15, 2019violation	Jan. 04, 2017violation	Jul. 29, 2016complaint	Feb. 09, 2016complaint	Dec. 11, 2013site	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)site	Jun. 30, 2018USD ($)
Commitments [Line Items]
FOVs (in sites)	1	1			1			12
Loss contingency accrual | $						$ 100,000		$ 100,000
Judicial District Court for the Parish of Cameron
Commitments [Line Items]
Number of claims filed (in claims) | complaint				1
Judicial District Court for the Parish of Vermillion
Commitments [Line Items]
Number of claims filed (in claims) | complaint			1
Loss on long-term purchase commitment | Muskie Proppant LLC
Commitments [Line Items]
Non-utilization fees, accrued damages year to date | $						$ 0	$ 0	$ 300,000	$ 900,000

COMMITTMENTS AND CONTINGENCIE_3

COMMITTMENTS AND CONTINGENCIES (Future Commitments) (Details) $ in Thousands	Jun. 30, 2019USD ($)MMBTU
Commitments [Line Items]
Remaining 2019 (in mmbtu) | MMBTU	493,000
2020 (in mmbtu) | MMBTU	276,000
2021 (in mmbtu) | MMBTU	179,000
2022 (in mmbtu) | MMBTU	70,000
2023 (in mmbtu) | MMBTU	42,000
Thereafter (in mmbtu) | MMBTU	25,000
Total (in mmbtu) | MMBTU	1,085,000
2020	$ 24,000
2021	24,000
Total	60,000
Transportation commitment
Commitments [Line Items]
Remaining 2019	122,128
2020	273,973
2021	273,011
2022	273,011
2023	268,209
Thereafter	2,283,229
Total	$ 3,493,561

COMMITTMENTS AND CONTINGENCIE_4

COMMITTMENTS AND CONTINGENCIES (Future Minimum Commitments) (Details) $ in Thousands	Jun. 30, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remaining 2019	$ 12,000
2020	24,000
2021	24,000
Total	$ 60,000

DERIVATIVE INSTRUMENTS (Narrati

DERIVATIVE INSTRUMENTS (Narrative) (Details) - 2019	1 Months Ended	6 Months Ended
	Dec. 31, 2018MMBTU$ / MMBTU	Jun. 30, 2019
Derivative [Line Items]
Counterparty option to extend the original terms, number of months		12 months
Daily volume (in MMBtu) | MMBTU	100,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	3.05

DERIVATIVE INSTRUMENTS (Schedul

DERIVATIVE INSTRUMENTS (Schedule of Derivative Instruments) (Details)	6 Months Ended
	Jun. 30, 2019MMBTU$ / bbl$ / MMBTUbbl
NYMEX Henry Hub Swap - 2019
Derivative [Line Items]
Daily Volume (MMBtu/day) | MMBTU	1,380,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	(2.81)
NYMEX Henry Hub Swap - 2019 | Short | Call Option
Derivative [Line Items]
Daily Volume (MMBtu/day) | MMBTU	30,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	(3.10)
NYMEX Henry Hub Swap - 2020
Derivative [Line Items]
Daily Volume (MMBtu/day) | MMBTU	204,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	(2.77)
NYMEX WTI Swap - 2019
Derivative [Line Items]
Daily Volume (Bbls/day) | bbl	6,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl	(60.81)
NYMEX WTI Swap - 2020
Derivative [Line Items]
Daily Volume (Bbls/day) | bbl	6,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl	(59.82)
Mont Belvieu C2 - 2019
Derivative [Line Items]
Daily Volume (Bbls/day) | bbl	1,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl	(18.48)
Mont Belvieu C3 Swap - 2019
Derivative [Line Items]
Daily Volume (Bbls/day) | bbl	4,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl	(29.02)
Mont Belvieu C5 Swap - 2019
Derivative [Line Items]
Daily Volume (Bbls/day) | bbl	1,000
Weighted average price (in usd per MMBtu or Bbl) | $ / bbl	(53.71)
Transco Zone 4 - 2019 | Long
Derivative [Line Items]
Daily Volume (MMBtu/day) | MMBTU	60,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	(0.05)
Transco Zone 4 - 2020 | Long
Derivative [Line Items]
Daily Volume (MMBtu/day) | MMBTU	60,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	(0.05)
Fixed Spread - 2020 | Long
Derivative [Line Items]
Daily Volume (MMBtu/day) | MMBTU	10,000
Weighted average price (in usd per MMBtu or Bbl) | $ / MMBTU	(0.54)

DERIVATIVE INSTRUMENTS (Derivat

DERIVATIVE INSTRUMENTS (Derivative Instruments in Financial Position) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Short-term derivative instruments - asset	$ 134,920	$ 21,352
Long-term derivative instruments - asset	5,036	0
Short-term derivative instruments - liability	198	20,401
Long-term derivative instruments - liability	$ 210	$ 13,992

DERIVATIVE INSTRUMENTS (Net (Lo

DERIVATIVE INSTRUMENTS (Net (Loss) Gain on Derivative Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative [Line Items]
Net gain (loss) on natural gas, oil, and NGLs derivatives	$ 171,140	$ (70,545)	$ 151,095	$ (87,074)
Natural gas derivatives
Derivative [Line Items]
Net gain (loss) on natural gas, oil, and NGLs derivatives	152,475	(31,194)	136,044	(40,890)
Oil derivatives
Derivative [Line Items]
Net gain (loss) on natural gas, oil, and NGLs derivatives	11,871	(24,419)	11,417	(33,566)
NGL derivatives
Derivative [Line Items]
Net gain (loss) on natural gas, oil, and NGLs derivatives	$ 6,794	$ (14,932)	$ 3,634	$ (12,618)

DERIVATIVE INSTRUMENTS (Sched_2

DERIVATIVE INSTRUMENTS (Schedule of Offsetting) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross assets presented in the consolidated balance sheet	$ 139,956	$ 21,352
Gross assets subject to mater netting agreement - assets	(408)	(19,289)
Net amount - assets	139,548	2,063
Gross liabilities presented in the consolidated balance sheet	(408)	(34,393)
Gross amounts subject to master netting agreement - liabilities	408	19,289
Net amount - liabilities	$ 0	$ (15,104)

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Liabilities:
Asset retirement obligation capitalized	$ 5,153	$ 909
Level 1
Assets:
Derivative Instruments	0		$ 0
Liabilities:
Derivative Instruments	0		0
Level 2
Assets:
Derivative Instruments	139,956		21,352
Liabilities:
Derivative Instruments	408		34,393
Level 3
Assets:
Derivative Instruments	0		0
Liabilities:
Derivative Instruments	$ 0		$ 0

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 28,426	$ 30,733
Senior notes | 6.625% senior unsecured notes due 2023
Debt Instrument [Line Items]
Unamortized debt issuance costs	4,000
Senior notes | 6.000% senior unsecured notes due 2024
Debt Instrument [Line Items]
Unamortized debt issuance costs	8,100
Senior notes | 6.375% senior unsecured notes due 2025
Debt Instrument [Line Items]
Unamortized debt issuance costs	11,700
Senior notes | 6.375% senior unsecured notes due 2026
Debt Instrument [Line Items]
Unamortized debt issuance costs	4,700
Carry value | Senior notes
Debt Instrument [Line Items]
Carrying value of notes	2,000,000
Fair value | Senior notes
Debt Instrument [Line Items]
Carrying value of notes	$ 1,600,000

REVENUE FROM CONTRACTS WITH C_2

REVENUE FROM CONTRACTS WITH CUSTOMERS (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Receivables from contracts with customers	$ 131.7	$ 210.2
Performance obligation period	However, settlement statements for certain sales may be received for 30 to 90 days after the date production is delivered, and as a result, the Company is required to estimate the amount of production that was delivered to the purchaser and the price that will be received for the sale of the product.
Maximum
Disaggregation of Revenue [Line Items]
Performance obligation period	P30D

LEASES (Narrative) (Details)

LEASES (Narrative) (Details) - USD ($)	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Lessee, Lease, Description [Line Items]
Operating lease assets	$ 19,334,000
Lease liability	72,913,000
Accumulated deficit	$ (548,170,000)		$ (845,368,000)
Weighted average remaining lease term	1 year 10 months 9 days
Weighted-average discount rate - operating leases	3.78%
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease assets		$ 110,000,000
Lease liability		110,000,000
Accumulated deficit		$ 0
Minimum
Lessee, Lease, Description [Line Items]
Lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lease term	5 years
Drilling Rig | Minimum
Lessee, Lease, Description [Line Items]
Lease term	1 year
Drilling Rig | Maximum
Lessee, Lease, Description [Line Items]
Lease term	2 years

LEASES (Maturities of Lease Lia

LEASES (Maturities of Lease Liabilities) (Details) $ in Thousands	Jun. 30, 2019USD ($)
Leases [Abstract]
Remaining 2019	$ 25,243
2020	27,481
2021	22,731
2022	115
2023	90
Thereafter	30
Total lease payments	75,690
Less: Imputed interest	(2,777)
Lease liability	$ 72,913

LEASES (Lease Cost) (Details)

LEASES (Lease Cost) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019USD ($)
Leases [Abstract]
Operating lease cost	$ 16,284
Operating lease cost - related party	11,220
Variable lease cost	960
Variable lease cost - related party	59,611
Short-term lease cost	183
Total lease cost	$ 88,258

LEASES (Other Information) (Det

LEASES (Other Information) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019USD ($)
Leases [Abstract]
Operating cash flows from operating leases	$ 120
Investing cash flow from operating leases	12,288
Investing cash flow from operating leases - related party	$ 43,925

INCOME TAXES (Details)

INCOME TAXES (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)
Income Tax Disclosure [Abstract]
Effective tax rate	(322.50%)	(152.20%)
Adjustment of deferred tax asset	$ 179.3
Years of cumulative pretax income		3 years
Deferred tax realizable	207.2	$ 207.2
Deferred taxes	27.7	27.7
Tax allowance, discrete adjustment		179.3
Foreign tax credits	$ 4.8	$ 4.8
Testing period		3 years

CONDENSED CONSOLIDATING FINAN_3

CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 20,777		$ 52,297
Accounts receivable - oil and natural gas sales	131,675		210,200
Accounts receivable - joint interest and other	46,645		22,497
Accounts receivable - intercompany	0		0
Prepaid expenses and other current assets	9,474		10,607
Short-term derivative instruments	134,920		21,352
Total current assets	343,491		316,953
Property and equipment:
Oil and natural gas properties	10,510,427		10,026,836
Other property and equipment	96,413		92,667
Accumulated depletion, depreciation, amortization and impairment	(4,882,729)		(4,640,098)
Property and equipment, net	5,724,111		5,479,405
Other assets:
Equity investments and investments in subsidiaries	119,307		236,121
Long-term derivative instruments	5,036		0
Deferred tax asset	179,331		0
Inventories	9,001		4,754
Operating lease assets	19,334
Operating lease assets - related parties	53,579
Other assets	12,280		13,803
Total other assets	397,868		254,678
Total assets	6,465,470		6,051,036
Current liabilities:
Accounts payable and accrued liabilities	493,830		518,380
Accounts payable - intercompany	0		0
Short-term derivative instruments	198		20,401
Current portion of operating lease liabilities	17,999
Current portion of operating lease liabilities - related parties	20,817
Current maturities of long-term debt	615		651
Total current liabilities	533,459		539,432
Long-term derivative instruments	210		13,992
Asset retirement obligation—long-term	88,491		79,952	$ 76,815
Deferred tax liability	3,127		3,127
Non-current operating lease liabilities	1,335
Non-current operating lease liabilities - related parties	32,762
Long-term debt, net of current maturities	2,198,678		2,086,765
Total liabilities	2,858,062		2,723,268
Stockholders’ equity:
Common stock	1,594		1,630
Paid-in capital	4,202,599		4,227,532
Accumulated other comprehensive loss	(48,615)		(56,026)
(Accumulated deficit) retained earnings	(548,170)		(845,368)
Total stockholders’ equity	3,607,408	$ 3,368,266	3,327,768	$ 3,195,199	$ 3,088,889	$ 3,101,614
Total liabilities and stockholders’ equity	6,465,470		6,051,036
Reportable legal entities | Parent
Current assets:
Cash and cash equivalents	10,940		25,585
Accounts receivable - oil and natural gas sales	4,116		146,075
Accounts receivable - joint interest and other	9,043		16,212
Accounts receivable - intercompany	819,584		671,633
Prepaid expenses and other current assets	5,948		8,433
Short-term derivative instruments	134,920		21,352
Total current assets	984,551		889,290
Property and equipment:
Oil and natural gas properties	1,352,894		7,044,550
Other property and equipment	92,343		91,916
Accumulated depletion, depreciation, amortization and impairment	(1,414,011)		(4,640,059)
Property and equipment, net	31,226		2,496,407
Other assets:
Equity investments and investments in subsidiaries	5,171,925		2,856,988
Long-term derivative instruments	5,036
Deferred tax asset	179,331
Inventories	188		3,620
Operating lease assets	19,334
Operating lease assets - related parties	53,579
Other assets	11,682		12,624
Total other assets	5,441,075		2,873,232
Total assets	6,456,852		6,258,929
Current liabilities:
Accounts payable and accrued liabilities	74,597		419,107
Accounts payable - intercompany	469,071		320,259
Short-term derivative instruments	198		20,401
Current portion of operating lease liabilities	17,999
Current portion of operating lease liabilities - related parties	20,817
Current maturities of long-term debt	615		651
Total current liabilities	583,297		760,418
Long-term derivative instruments	210		13,992
Asset retirement obligation—long-term	30,035		66,859
Deferred tax liability	3,127		3,127
Non-current operating lease liabilities	1,335
Non-current operating lease liabilities - related parties	32,762
Long-term debt, net of current maturities	2,198,678		2,086,765
Total liabilities	2,849,444		2,931,161
Stockholders’ equity:
Common stock	1,594		1,630
Paid-in capital	4,202,599		4,227,532
Accumulated other comprehensive loss	(48,615)		(56,026)
(Accumulated deficit) retained earnings	(548,170)		(845,368)
Total stockholders’ equity	3,607,408		3,327,768
Total liabilities and stockholders’ equity	6,456,852		6,258,929
Reportable legal entities | Guarantors
Current assets:
Cash and cash equivalents	9,799		26,711
Accounts receivable - oil and natural gas sales	127,559		64,125
Accounts receivable - joint interest and other	37,602		6,285
Accounts receivable - intercompany	433,776		319,464
Prepaid expenses and other current assets	3,451		2,174
Short-term derivative instruments	0		0
Total current assets	612,187		418,759
Property and equipment:
Oil and natural gas properties	9,158,193		2,983,015
Other property and equipment	751		751
Accumulated depletion, depreciation, amortization and impairment	(3,468,663)		(39)
Property and equipment, net	5,690,281		2,983,727
Other assets:
Equity investments and investments in subsidiaries			0
Long-term derivative instruments	0
Deferred tax asset	0
Inventories	8,813		1,134
Operating lease assets	0
Operating lease assets - related parties	0
Other assets	598		1,178
Total other assets	9,411		2,312
Total assets	6,311,879		3,404,798
Current liabilities:
Accounts payable and accrued liabilities	419,190		99,273
Accounts payable - intercompany	780,600		670,708
Short-term derivative instruments	0		0
Current portion of operating lease liabilities	0
Current portion of operating lease liabilities - related parties	0
Current maturities of long-term debt	0		0
Total current liabilities	1,199,790		769,981
Long-term derivative instruments	0		0
Asset retirement obligation—long-term	58,456		13,093
Deferred tax liability	0		0
Non-current operating lease liabilities	0
Non-current operating lease liabilities - related parties	0
Long-term debt, net of current maturities	0		0
Total liabilities	1,258,246		783,074
Stockholders’ equity:
Common stock	0		0
Paid-in capital	4,170,574		1,915,598
Accumulated other comprehensive loss	0		0
(Accumulated deficit) retained earnings	883,059		706,126
Total stockholders’ equity	5,053,633		2,621,724
Total liabilities and stockholders’ equity	6,311,879		3,404,798
Reportable legal entities | Non-Guarantors
Current assets:
Cash and cash equivalents	38		1
Accounts receivable - oil and natural gas sales	0		0
Accounts receivable - joint interest and other	0		0
Accounts receivable - intercompany	0		0
Prepaid expenses and other current assets	75		0
Short-term derivative instruments	0		0
Total current assets	113		1
Property and equipment:
Oil and natural gas properties	69		0
Other property and equipment	3,319		0
Accumulated depletion, depreciation, amortization and impairment	(55)		0
Property and equipment, net	3,333		0
Other assets:
Equity investments and investments in subsidiaries	51,607		44,259
Long-term derivative instruments	0
Deferred tax asset	0
Inventories	0		0
Operating lease assets	0
Operating lease assets - related parties	0
Other assets	0		0
Total other assets	51,607		44,259
Total assets	55,053		44,260
Current liabilities:
Accounts payable and accrued liabilities	43		0
Accounts payable - intercompany	3,689		130
Short-term derivative instruments	0		0
Current portion of operating lease liabilities	0
Current portion of operating lease liabilities - related parties	0
Current maturities of long-term debt	0		0
Total current liabilities	3,732		130
Long-term derivative instruments	0		0
Asset retirement obligation—long-term	0		0
Deferred tax liability	0		0
Non-current operating lease liabilities	0
Non-current operating lease liabilities - related parties	0
Long-term debt, net of current maturities	0		0
Total liabilities	3,732		130
Stockholders’ equity:
Common stock	0		0
Paid-in capital	262,059		261,626
Accumulated other comprehensive loss	(46,527)		(53,783)
(Accumulated deficit) retained earnings	(164,211)		(163,713)
Total stockholders’ equity	51,321		44,130
Total liabilities and stockholders’ equity	55,053		44,260
Eliminations
Current assets:
Cash and cash equivalents	0		0
Accounts receivable - oil and natural gas sales	0		0
Accounts receivable - joint interest and other	0		0
Accounts receivable - intercompany	(1,253,360)		(991,097)
Prepaid expenses and other current assets	0		0
Short-term derivative instruments	0		0
Total current assets	(1,253,360)		(991,097)
Property and equipment:
Oil and natural gas properties	(729)		(729)
Other property and equipment	0		0
Accumulated depletion, depreciation, amortization and impairment	0		0
Property and equipment, net	(729)		(729)
Other assets:
Equity investments and investments in subsidiaries	(5,104,225)		(2,665,126)
Long-term derivative instruments	0
Deferred tax asset	0
Inventories	0		0
Operating lease assets	0
Operating lease assets - related parties	0
Other assets	0		1
Total other assets	(5,104,225)		(2,665,125)
Total assets	(6,358,314)		(3,656,951)
Current liabilities:
Accounts payable and accrued liabilities	0		0
Accounts payable - intercompany	(1,253,360)		(991,097)
Short-term derivative instruments	0		0
Current portion of operating lease liabilities	0
Current portion of operating lease liabilities - related parties	0
Current maturities of long-term debt	0		0
Total current liabilities	(1,253,360)		(991,097)
Long-term derivative instruments	0		0
Asset retirement obligation—long-term	0		0
Deferred tax liability	0		0
Non-current operating lease liabilities	0
Non-current operating lease liabilities - related parties	0
Long-term debt, net of current maturities	0		0
Total liabilities	(1,253,360)		(991,097)
Stockholders’ equity:
Common stock	0		0
Paid-in capital	(4,432,633)		(2,177,224)
Accumulated other comprehensive loss	46,527		53,783
(Accumulated deficit) retained earnings	(718,848)		(542,413)
Total stockholders’ equity	(5,104,954)		(2,665,854)
Total liabilities and stockholders’ equity	$ (6,358,314)		$ (3,656,951)

CONDENSED CONSOLIDATING FINAN_4

CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues:
Total revenues	$ 458,994		$ 252,740		$ 779,572	$ 578,132
Costs and expenses:
Lease operating expenses	22,388		22,912		42,195	41,818
Production taxes	8,098		7,659		16,019	14,513
Midstream gathering and processing expenses	72,015		71,440		142,297	135,633
Depreciation, depletion and amortization	124,951		121,915		243,384	232,933
General and administrative expenses	13,265		14,008		24,823	27,107
Accretion expense	1,359		1,015		2,426	2,019
Total costs and expenses	242,076		238,949		471,144	454,023
INCOME (LOSS) FROM OPERATIONS	216,918		13,791		308,428	124,109
OTHER EXPENSE (INCOME):
Interest expense	34,880		33,704		69,000	67,669
Interest income	(159)		(33)		(311)	(70)
Insurance proceeds	(83)		(231)		(83)	(231)
Gain on sale of equity method investments	0		(122,035)		0	(122,035)
(Income) loss from equity method investments and investments in subsidiaries	125,582		(8,888)		121,309	(22,424)
Other expense (income)	1,073		(45)		646	(140)
Total other (income) expense	161,293		(97,528)		190,561	(77,231)
INCOME (LOSS) BEFORE INCOME TAXES	55,625		111,319		117,867	201,340
INCOME TAX BENEFIT	(179,331)		0		(179,331)	(69)
NET INCOME (LOSS)	234,956	$ 62,242	111,319	$ 90,090	297,198	201,409
Parent
OTHER EXPENSE (INCOME):
Insurance proceeds	(83)				(83)
Guarantors
OTHER EXPENSE (INCOME):
Insurance proceeds	0				0
Non-Guarantors
OTHER EXPENSE (INCOME):
Insurance proceeds	0				0
Reportable legal entities | Parent
Revenues:
Total revenues	280,291		146,774		466,537	360,335
Costs and expenses:
Lease operating expenses	12,256		16,593		27,149	30,424
Production taxes	2,820		4,793		6,081	8,804
Midstream gathering and processing expenses	28,121		52,542		71,420	98,208
Depreciation, depletion and amortization	80,132		121,915		198,564	232,932
General and administrative expenses	16,745		14,975		28,977	28,786
Accretion expense	438		795		1,389	1,585
Total costs and expenses	140,512		211,613		333,580	400,739
INCOME (LOSS) FROM OPERATIONS	139,779		(64,839)		132,957	(40,404)
OTHER EXPENSE (INCOME):
Interest expense	35,835		34,663		70,259	69,056
Interest income	(120)		(27)		(267)	(58)
Insurance proceeds			(231)			(231)
Gain on sale of equity method investments			(25,616)			(25,616)
(Income) loss from equity method investments and investments in subsidiaries	47,449		(183,901)		(55,465)	(283,765)
Other expense (income)	1,073		(1,046)		646	(1,130)
Total other (income) expense	84,154		(176,158)		15,090	(241,744)
INCOME (LOSS) BEFORE INCOME TAXES	55,625		111,319		117,867	201,340
INCOME TAX BENEFIT	(179,331)		0		(179,331)	(69)
NET INCOME (LOSS)	234,956		111,319		297,198	201,409
Reportable legal entities | Guarantors
Revenues:
Total revenues	178,703		105,966		313,035	217,797
Costs and expenses:
Lease operating expenses	10,132		6,319		15,046	11,394
Production taxes	5,278		2,866		9,938	5,709
Midstream gathering and processing expenses	43,894		18,898		70,877	37,425
Depreciation, depletion and amortization	44,764		0		44,765	1
General and administrative expenses	(3,583)		(968)		(4,258)	(1,681)
Accretion expense	921		220		1,037	434
Total costs and expenses	101,406		27,335		137,405	53,282
INCOME (LOSS) FROM OPERATIONS	77,297		78,631		175,630	164,515
OTHER EXPENSE (INCOME):
Interest expense	(955)		(959)		(1,259)	(1,387)
Interest income	(39)		(6)		(44)	(12)
Insurance proceeds			0			0
Gain on sale of equity method investments			(96,419)			(96,419)
(Income) loss from equity method investments and investments in subsidiaries	0		(336)		0	(693)
Other expense (income)	0		1		0	(10)
Total other (income) expense	(994)		(97,719)		(1,303)	(98,521)
INCOME (LOSS) BEFORE INCOME TAXES	78,291		176,350		176,933	263,036
INCOME TAX BENEFIT	0		0		0	0
NET INCOME (LOSS)	78,291		176,350		176,933	263,036
Reportable legal entities | Non-Guarantors
Revenues:
Total revenues	0		0		0	0
Costs and expenses:
Lease operating expenses	0		0		0	0
Production taxes	0		0		0	0
Midstream gathering and processing expenses	0		0		0	0
Depreciation, depletion and amortization	55		0		55	0
General and administrative expenses	103		1		104	2
Accretion expense	0		0		0	0
Total costs and expenses	158		1		159	2
INCOME (LOSS) FROM OPERATIONS	(158)		(1)		(159)	(2)
OTHER EXPENSE (INCOME):
Interest expense	0		0		0	0
Interest income	0		0		0	0
Insurance proceeds			0			0
Gain on sale of equity method investments			0			0
(Income) loss from equity method investments and investments in subsidiaries	(54)		228		339	558
Other expense (income)	0		0		0	0
Total other (income) expense	(54)		228		339	558
INCOME (LOSS) BEFORE INCOME TAXES	(104)		(229)		(498)	(560)
INCOME TAX BENEFIT	0		0		0	0
NET INCOME (LOSS)	(104)		(229)		(498)	(560)
Eliminations
Revenues:
Total revenues	0		0		0	0
Costs and expenses:
Lease operating expenses	0		0		0	0
Production taxes	0		0		0	0
Midstream gathering and processing expenses	0		0		0	0
Depreciation, depletion and amortization	0		0		0	0
General and administrative expenses	0		0		0	0
Accretion expense	0		0		0	0
Total costs and expenses	0		0		0	0
INCOME (LOSS) FROM OPERATIONS	0		0		0	0
OTHER EXPENSE (INCOME):
Interest expense	0		0		0	0
Interest income	0		0		0	0
Insurance proceeds	0		0		0	0
Gain on sale of equity method investments			0			0
(Income) loss from equity method investments and investments in subsidiaries	78,187		175,121		176,435	261,476
Other expense (income)	0		1,000		0	1,000
Total other (income) expense	78,187		176,121		176,435	262,476
INCOME (LOSS) BEFORE INCOME TAXES	(78,187)		(176,121)		(176,435)	(262,476)
INCOME TAX BENEFIT	0		0		0	0
NET INCOME (LOSS)	$ (78,187)		$ (176,121)		$ (176,435)	$ (262,476)

CONDENSED CONSOLIDATING FINAN_5

CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Statements of Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ 234,956	$ 62,242	$ 111,319	$ 90,090	$ 297,198	$ 201,409
Foreign currency translation adjustment	3,610		(3,364)		7,411	(8,867)
Other comprehensive income (loss)	3,610	$ 3,801	(3,364)	$ (5,503)	7,411	(8,867)
Comprehensive income	238,566		107,955		304,609	192,542
Reportable legal entities | Parent
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	234,956		111,319		297,198	201,409
Foreign currency translation adjustment	3,610		(3,364)		7,411	(8,867)
Other comprehensive income (loss)	3,610		(3,364)		7,411	(8,867)
Comprehensive income	238,566		107,955		304,609	192,542
Reportable legal entities | Guarantors
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	78,291		176,350		176,933	263,036
Foreign currency translation adjustment	61		14		155	(173)
Other comprehensive income (loss)	61		14		155	(173)
Comprehensive income	78,352		176,364		177,088	262,863
Reportable legal entities | Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(104)		(229)		(498)	(560)
Foreign currency translation adjustment	3,549		(3,378)		7,256	(8,694)
Other comprehensive income (loss)	3,549		(3,378)		7,256	(8,694)
Comprehensive income	3,445		(3,607)		6,758	(9,254)
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(78,187)		(176,121)		(176,435)	(262,476)
Foreign currency translation adjustment	(3,610)		3,364		(7,411)	8,867
Other comprehensive income (loss)	(3,610)		3,364		(7,411)	8,867
Comprehensive income	$ (81,797)		$ (172,757)		$ (183,846)	$ (253,609)

CONDENSED CONSOLIDATING FINAN_6

CONDENSED CONSOLIDATING FINANCIAL INFORMATION (Cash Flows) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	$ 308,989	$ 411,044
Net cash (used in) provided by investing activities	(419,445)	(360,465)
Net cash provided by (used in) financing activities	78,936	(30,906)
Net (decrease) increase in cash, cash equivalents and restricted cash	(31,520)	19,673
Cash, cash equivalents and restricted cash at beginning of period	52,297	99,557
Cash, cash equivalents and restricted cash at end of period	20,777	119,230
Reportable legal entities | Parent
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	230,776	370,965
Net cash (used in) provided by investing activities	(324,357)	(327,362)
Net cash provided by (used in) financing activities	78,936	(30,906)
Net (decrease) increase in cash, cash equivalents and restricted cash	(14,645)	12,697
Cash, cash equivalents and restricted cash at beginning of period	25,585	67,908
Cash, cash equivalents and restricted cash at end of period	10,940	80,605
Reportable legal entities | Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	74,857	40,078
Net cash (used in) provided by investing activities	(91,769)	(33,103)
Net cash provided by (used in) financing activities	0	0
Net (decrease) increase in cash, cash equivalents and restricted cash	(16,912)	6,975
Cash, cash equivalents and restricted cash at beginning of period	26,711	31,649
Cash, cash equivalents and restricted cash at end of period	9,799	38,624
Reportable legal entities | Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	3,355	0
Net cash (used in) provided by investing activities	(3,751)	(1,569)
Net cash provided by (used in) financing activities	433	1,570
Net (decrease) increase in cash, cash equivalents and restricted cash	37	1
Cash, cash equivalents and restricted cash at beginning of period	1	0
Cash, cash equivalents and restricted cash at end of period	38	1
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	1	1
Net cash (used in) provided by investing activities	432	1,569
Net cash provided by (used in) financing activities	(433)	(1,570)
Net (decrease) increase in cash, cash equivalents and restricted cash	0	0
Cash, cash equivalents and restricted cash at beginning of period	0	0
Cash, cash equivalents and restricted cash at end of period	$ 0	$ 0

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions	1 Months Ended
	Dec. 31, 2018	Jul. 31, 2019
Subsequent Event [Line Items]
Total consideration	$ 19.7
Payments to acquire businesses	$ 9.2
Commodity pricing threshold	2 years
Revolving Credit Facility | Subsequent Event
Subsequent Event [Line Items]
Aggregate principal amount		$ 104.4
Repurchase amount		$ 80.3