Assumption used in valuing an instrument.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Accumulated expirations or loss on unproved oil and gas properties.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

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

+ References

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Period Type:	instant

- References

No definition available.

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- Definition

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

+ References

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- Definition

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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Balance Type:	debit
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- Definition

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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- References

No definition available.

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- Definition

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.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Period Type:	duration

- 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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-SubTopic 10
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-Paragraph 2
-Subparagraph (a)
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- Details

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Fair Value (Details) $ in Thousands	3 Months Ended		9 Months Ended
Fair Value (Details) $ in Thousands	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 23, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jun. 17, 2020 USD ($)
Assets
Derivative Assets, Fair Value, Gross Asset	$ 30,610		$ 30,610			$ 54,353
Liabilities
Derivative Liability, Fair Value, Gross Liability	(642,699)		(642,699)			(222,520)
Oil and Gas Property [Abstract]
Property, Plant, and Equipment, Fair Value Disclosure	0		0			$ 0
Impairment of Proved Oil and Gas Properties	0	$ 0	0	$ 956,650
Abandonment and impairment of unproved properties	8,750	8,750	26,250	50,613
Impairment of Oil and Gas Properties	$ 8,750	$ 8,750	$ 26,250	$ 1,007,263
1.50% Senior Secured Convertible Notes Due 2021
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	1.50%		1.50%			1.50%
Senior Notes, Principal amount	$ 0		$ 0			$ 65,485
Long-term Debt, Fair Value	$ 0		$ 0			$ 61,449
10.0% Senior Secured Notes due 2025
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	10.00%		10.00%			10.00%
Senior Notes, Principal amount	$ 446,675		$ 446,675			$ 446,675	$ 446,700
Long-term Debt, Fair Value	$ 498,212		$ 498,212			$ 482,887
6.125% Senior Unsecured Notes due 2022
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.125%		6.125%			6.125%
Senior Notes, Principal amount	$ 0		$ 0			$ 212,403
Long-term Debt, Fair Value	$ 0		$ 0			$ 205,379
5.0% Senior Unsecured Notes due 2024
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	5.00%		5.00%			5.00%
Senior Notes, Principal amount	$ 104,769		$ 104,769			$ 277,034
Long-term Debt, Fair Value	$ 104,392		$ 104,392			$ 240,072
5.625% Senior Unsecured Notes due 2025
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	5.625%		5.625%			5.625%
Senior Notes, Principal amount	$ 349,118		$ 349,118			$ 349,118
Long-term Debt, Fair Value	$ 351,935		$ 351,935			$ 289,401
6.75% Senior Unsecured Notes due 2026
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.75%		6.75%			6.75%
Senior Notes, Principal amount	$ 419,235		$ 419,235			$ 419,235
Long-term Debt, Fair Value	$ 428,773		$ 428,773			$ 342,385
6.625% Senior Unsecured Notes due 2027
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.625%		6.625%			6.625%
Senior Notes, Principal amount	$ 416,791		$ 416,791			$ 416,791
Long-term Debt, Fair Value	$ 426,952		$ 426,952			$ 331,220
6.5% Senior Unsecured Notes Due 2028
Debt Instrument, Fair Value Disclosure [Abstract]
Senior Notes, interest rate, stated percentage	6.50%		6.50%		6.50%	6.50%
Senior Notes, Principal amount	$ 400,000		$ 400,000		$ 400,000	$ 0
Long-term Debt, Fair Value	414,352		414,352			0
Fair Value, Nonrecurring \| Measurement Input, Discount Rate \| Oil and Gas Properties
Oil and Gas Property [Abstract]
Fair Value Assumptions, Measurement Input		0.11		0.11
Not Designated as Hedging Instrument \| Fair Value, Recurring \| Fair Value, Inputs, Level 1
Assets
Derivative Assets, Fair Value, Gross Asset	0		0			0
Liabilities
Derivative Liability, Fair Value, Gross Liability	0		0			0
Not Designated as Hedging Instrument \| Fair Value, Recurring \| Fair Value, Inputs, Level 2
Assets
Derivative Assets, Fair Value, Gross Asset	30,610		30,610			54,353
Liabilities
Derivative Liability, Fair Value, Gross Liability	642,699		642,699			222,520
Not Designated as Hedging Instrument \| Fair Value, Recurring \| Fair Value, Inputs, Level 3
Assets
Derivative Assets, Fair Value, Gross Asset	0		0			0
Liabilities
Derivative Liability, Fair Value, Gross Liability	$ 0		$ 0			$ 0