Depreciation, depletion, amortization and accretion for continuing operations.

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- Definition

Summary of significant accounting policies.

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- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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- Definition

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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- Definition

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

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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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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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended			9 Months Ended
	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Segment	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Jul. 06, 2015
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	$ 63,483,000			$ 63,483,000		$ 77,402,000
Depreciation, depletion, amortization and accretion	53,153,000		$ 45,456,000	140,058,000	$ 113,950,000
Impairment of oil and gas properties				6,849,000
ARO liability current	2,867,000			$ 2,867,000
Number of operating segment \| Segment				1
Amortization of deferred financing costs and debt discount	$ 900,000		900,000	$ 3,000,000.0	3,200,000
Wrote off unamortized deferred financing costs		$ 200,000
8.875% Senior Unsecured Notes Due 2023 [Member]
Summary Of Significant Accounting Policies [Line Items]
Debt instrument interest rate	8.875%			8.875%			8.875%
Accrued Liabilities [Member]
Summary Of Significant Accounting Policies [Line Items]
ARO liability current	$ 2,900,000			$ 2,900,000		2,000,000.0
Oil and Gas Properties [Member]
Summary Of Significant Accounting Policies [Line Items]
Depreciation, depletion, amortization and accretion	52,800,000		44,900,000	138,900,000	112,400,000
Other property and equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Depreciation	400,000		600,000	$ 1,200,000	1,600,000
Other property and equipment [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, expected lives				5 years
Other property and equipment [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, expected lives				40 years
Proved Oil And Gas Properties [Member] \| Utica and Marcellus Shales [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairment of oil and gas properties	0		0	$ 0	0
Unproved Oil And Gas Properties [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairment of oil and gas properties	11,000,000.0		$ 14,100,000	30,300,000	$ 36,200,000
Commodity Contract [Member] \| Not Designated as Hedging Instrument [Member]
Summary Of Significant Accounting Policies [Line Items]
Fair value of derivative contracts	(47,700,000)			(47,700,000)		27,100,000
Revenue From Contract With Customer [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	$ 53,500,000			$ 53,500,000		$ 63,700,000