Assumption used in valuing an instrument.

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- Definition

The impairment expense recorded to reduce the value of proved oil and gas assets.

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No definition available.

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Accumulated expirations or loss on unproved oil and gas properties.

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No definition available.

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No definition available.

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Warrant Triggering Date - Amount

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No definition available.

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Warrants Percent of Outstanding Stock

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No definition available.

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- Definition

Amount of increase in additional paid in capital (APIC) resulting from the issuance of warrants. Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 20
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-Subparagraph (SX 210.3-04)
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- References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

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No definition available.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Fair Value Measurements (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
	Jun. 17, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 20, 2018	Sep. 12, 2016	Aug. 12, 2016	May 21, 2015	Nov. 17, 2014	May 20, 2013
Assets:
Derivative Assets, Fair Value, Gross Asset		$ 54,353	$ 75,808
Liabilities:
Derivative Liability, Fair Value, Gross Liability		(222,520)	(54,290)
Oil and Gas Properties
Impairment of proved oil and gas properties and related support equipment		956,700	0	$ 0
Abandonment and impairment of unproved properties		59,300	33,800	49,900
Impairment		1,016,013	33,842	$ 49,889
Property, Plant, and Equipment, Fair Value Disclosure		0	0
Debt Instrument, Fair Value Disclosure [Abstract]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	5,900
Warrants Percent of Outstanding Stock	5.00%
Exercise price of warrants	$ 0.01
Warrant triggering date - amount	$ 1,000,000
Issuance of warrants	21,500	$ 21,520
1.50% Senior Secured Convertible Notes Due 2021 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage		1.50%
Principal amount		$ 65,485	0
Fair value		$ 61,449	0
10.0% Senior Secured Notes due 2025 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage		10.00%
Principal amount	$ 446,700	$ 446,675	0
Fair value		$ 482,887	$ 0
6.125% Senior Unsecured Notes Due 2022 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.125%	6.125%	6.125%						6.125%
Principal amount		$ 212,403	$ 476,796						$ 600,000
Fair value		$ 205,379	$ 481,564
5.0% Senior Unsecured Notes Due 2024 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	5.00%	5.00%	5.00%							5.00%
Principal amount		$ 277,034	$ 500,000							$ 500,000
Fair value		$ 240,072	$ 479,815
5.625% Senior Unsecured Notes Due 2025 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	5.625%	5.625%	5.625%					5.625%
Principal amount		$ 349,118	$ 500,000					$ 500,000
Fair value		$ 289,401	$ 475,835
6.75% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.75%	6.75%	6.75%			6.75%
Principal amount		$ 419,235	$ 500,000			$ 500,000
Fair value		$ 342,385	$ 494,860
6.625% Senior Unsecured Notes Due 2027 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.625%	6.625%	6.625%		6.625%
Principal amount		$ 416,791	$ 500,000		$ 500,000
Fair value		$ 331,220	$ 493,750
1.50% Senior Unsecured Convertible Notes Due 2021 [Member]
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage		1.50%	1.50%
Principal amount		$ 0	$ 172,500				$ 172,500
Fair value		$ 0	164,430
Fair Value, Nonrecurring [Member] \| Measurement Input, Discount Rate [Member] \| Oil and Gas Properties [Member]
Oil and Gas Properties
Fair value assumptions, measurement input		0.11
Not Designated as Hedging Instrument [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets:
Derivative Assets, Fair Value, Gross Asset		$ 0	0
Liabilities:
Derivative Liability, Fair Value, Gross Liability		0	0
Not Designated as Hedging Instrument [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
Derivative Assets, Fair Value, Gross Asset		54,353	75,808
Liabilities:
Derivative Liability, Fair Value, Gross Liability		222,520	54,290
Not Designated as Hedging Instrument [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets:
Derivative Assets, Fair Value, Gross Asset		0	0
Liabilities:
Derivative Liability, Fair Value, Gross Liability		$ 0	$ 0