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- Definition

Commitments And Contingencies [Line Items]

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- Definition

Oil and Gas Delivery Commitments and Contracts, Maximum Term

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- Definition

Operating Leases, Future Minimum Payments Due, Increase

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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-Name Accounting Standards Codification
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-Section 50
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-Section 50
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- Definition

Total amount of product committed to be supplied under existing contracts or agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1207
-Paragraph (a)
-Subparagraph (2)

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

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- Definition

The amount of expenses related to oil and gas producing activities.

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- Definition

The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

+ References

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Commitments and Contingencies - Additional Information (Detail) $ in Millions		12 Months Ended
	Mar. 23, 2017 USD ($)	Dec. 31, 2017 USD ($) MBbls	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 MMcf	Oct. 01, 2017 USD ($) ft²
Commitments And Contingencies [Line Items]
Rental expense		$ 5.1	$ 6.3	$ 7.2
Long term commitments
Commitments And Contingencies [Line Items]
Contract term, maximum		10 years
Crude oil \| Long term commitments
Commitments And Contingencies [Line Items]
Minimum quantity of delivery \| MBbls		60,800
Natural gas \| Long term commitments
Commitments And Contingencies [Line Items]
Minimum quantity of delivery		21,600			189,900
Fresh Water \| Long term commitments
Commitments And Contingencies [Line Items]
Minimum quantity to be purchased \| MBbls		18,400
Volume Commitment Agreement
Commitments And Contingencies [Line Items]
Transportation and purchase costs incurred		$ 15.0	$ 16.1	$ 7.3
Pending Litigation \| Mirada Litigation
Commitments And Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	$ 100.0
Office Space Lease Agreement
Commitments And Contingencies [Line Items]
Additional rentable area (sq ft) \| ft²						8,915
Total future minimum rental commitments						$ 33.3