Fair Value Measurements - Nonrecurring (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Fair Value Measurements [Line Items]
Proved Oil and Gas Properties, Carrying Value, Before Impairment	$ 1,700,000
Unproved Oil and Gas Properties, Net Book Value Prior to Impairment	256,000
Proved Oil and Gas Properties
Fair Value Measurements [Line Items]
Impairment of Oil and Gas Properties	1,188,566	$ 0
Proved Oil and Gas Properties \| Level 3
Fair Value Measurements [Line Items]
Oil and Gas Property, Successful Effort Method, Net	500,000
Unproved Oil and Gas Properties
Fair Value Measurements [Line Items]
Impairment of Oil and Gas Properties	76,298	$ 0
Unproved Oil and Gas Properties \| Level 3
Fair Value Measurements [Line Items]
Oil and Gas Property, Successful Effort Method, Net	$ 179,700

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

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

+ References

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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
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 360
-Section 35
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=66906256&loc=d3e66150-109466

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10.(b))
-URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862

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