Costs incurred acquisition of unevaluated acreage and other assets.

No definition available.

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- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

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- Definition

Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have proved reserves.

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- Definition

Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have unproved reserves.

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- Definition

The fair value of assets acquired in noncash investing or financing activities.

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- Definition

The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced.

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- Definition

The cash outflow for acquisition of buildings (properties) whether for investment or use.

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The cash outflow to purchase of mineral interests in oil and gas properties for use in the normal oil and gas operations and not intended for resale.

+ References

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Acquisitions and Divestitures - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended	9 Months Ended
	Aug. 02, 2017	Jun. 15, 2017	Jun. 30, 2017	Mar. 31, 2018	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Acquisition of oil and gas properties					$ 4,762	$ 109,031
Battlecat Oil & Gas, LLC
Business Acquisition [Line Items]
Purchase consideration of oil and gas properties		$ 59,800
Acquisition of oil and gas properties		55,000
Purchase consideration paid to acquire proved reserves		56,300
Purchase consideration paid to acquire unproved reserves		2,900
Purchase consideration paid to acquire unevaluated acreage and other assets		600
Asset retirement obligations recorded with the acquisition of properties		200
Fair value of net assets acquired		59,600
Acquisition costs		1,500
SN Marquis LLC
Business Acquisition [Line Items]
Purchase consideration of oil and gas properties		50,000
Acquisition of oil and gas properties		44,000
Purchase consideration paid to acquire proved reserves		48,000
Purchase consideration paid to acquire unproved reserves		600
Purchase consideration paid to acquire unevaluated acreage and other assets		1,400
Asset retirement obligations recorded with the acquisition of properties		1,900
Fair value of net assets acquired		48,100
Acquisition costs		$ 1,200
Series B Convertible Participating Preferred Stock \| Battlecat Oil & Gas, LLC
Business Acquisition [Line Items]
Number of shares issued in connection with acquisition		1,184,632	1,184,632
Preferred Stock, par value (in dollars per share)		$ 0.001
Value of shares issued in connection with acquisition		$ 4,800
Series B Convertible Participating Preferred Stock \| SN Marquis LLC
Business Acquisition [Line Items]
Number of shares issued in connection with acquisition		1,500,000	1,500,000
Value of shares issued in connection with acquisition		$ 6,000
Fort Worth, Texas
Business Acquisition [Line Items]
Acquisition price of an office building	$ 10,000
Fort Worth, Texas \| Other Expense
Business Acquisition [Line Items]
Impairment charge				$ 1,600