Fair Value Measurements [Line Items]

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- Definition

Proved Oil and Gas Properties, Net Book Value Prior to Impairment

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method.

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-Publisher FASB
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Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Fair Value Measurements [Line Items]
Proved Oil and Gas Properties, Carrying Value, Before Impairment		$ 1,700,000,000
Principal amount	$ 800,000,000			$ 800,000,000		$ 765,000,000
7.0% Senior Notes
Fair Value Measurements [Line Items]
Debt, stated interest rate	7.00%			7.00%
Debt, fair value	$ 286,100,000			$ 286,100,000		335,000,000.0
Principal amount	$ 350,000,000			$ 350,000,000		350,000,000
8.75% Senior Notes
Fair Value Measurements [Line Items]
Debt, stated interest rate	8.75%			8.75%
Debt, fair value	$ 147,100,000			$ 147,100,000		251,200,000
Principal amount	275,000,000			275,000,000		275,000,000
Amended Credit Facility
Fair Value Measurements [Line Items]
Principal amount	175,000,000			175,000,000		$ 140,000,000
Proved Oil and Gas Properties
Fair Value Measurements [Line Items]
Impairment of Oil and Gas Properties	0	1,200,000,000	$ 0	1,188,566,000	$ 0
Unproved Oil and Gas Properties
Fair Value Measurements [Line Items]
Impairment of Oil and Gas Properties	$ 0	76,300,000	$ 0	$ 76,298,000	$ 0
Level 3 \| Proved Oil and Gas Properties
Fair Value Measurements [Line Items]
Oil and Gas Property, Successful Effort Method, Net		500,000,000
Oil and Gas Property, Successful Effort Method, Net		500,000,000
Level 3 \| Unproved Oil and Gas Properties
Fair Value Measurements [Line Items]
Oil and Gas Property, Successful Effort Method, Net		179,700,000
Oil and Gas Property, Successful Effort Method, Net		$ 179,700,000