Contract cancellable notice term.

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Contract cash settlement max days.

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Final Number Of Potential Performance Shares Issuable Maximum.

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Final Number Of Potential Performance Shares Issuable Minimum.

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Number of performance share units outstanding.

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Number of primary products.

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Operations and summary of significant accounting policies.

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Performance share units outstanding weighted average grant date fair value.

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Share based compensation arrangement by share based payment award equity instruments other than options unrecognized compensation cost.

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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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Net fair value of all derivative instruments designated as cash flow hedging instruments, which is ordinarily reflected within other comprehensive income.

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The average cap rate on a group of price risk derivatives such as caps or collars. A payment or receipt is triggered if the market rate exceeds the cap rate on the contract.

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The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

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The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Nominal energy measure used to calculate payments on a derivative instrument.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Fair value of the amount outstanding under the credit facility.

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Amount of noncash expense for share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information 2 (Detail)		1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 08, 2021 $ / shares shares	Aug. 04, 2021 MMBTU $ / MMBTU	Jun. 30, 2021 USD ($) $ / shares $ / EquityUnit shares	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) product $ / shares $ / EquityUnit shares	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) shares
Operations And Summary Of Significant Accounting Policies [Line Items]
Fair value of derivative net liability			$ 1,000,000.0		$ 1,000,000.0
Cash flow hedges derivative instruments			0		0
Stock-based compensation expense recognized					$ 3,489,000	$ 2,982,000
Number of primary products \| product					2
Contract cash settlement max days					25 days
Contract cancellable notice term					30 days
Oil and gas sales			$ 144,358,000		$ 144,358,000		$ 125,016,000
Natural Gas Swap Contract \| Subsequent Event
Operations And Summary Of Significant Accounting Policies [Line Items]
Volume (in MMBTU) \| MMBTU		2,750,000
Average price (in dollars per MMBtu) \| $ / MMBTU		3.00
Natural Gas Collar Contract \| Subsequent Event
Operations And Summary Of Significant Accounting Policies [Line Items]
Volume (in MMBTU) \| MMBTU		6,350,000
Average floor \| $ / MMBTU		2.85
Average ceiling \| $ / MMBTU		5.13
Restricted Stock
Operations And Summary Of Significant Accounting Policies [Line Items]
Granted (in shares) \| shares	473,162
Value per share (in dollars per share) \| $ / shares	$ 6.05
Shares of unvested restricted stock outstanding (in shares) \| shares			1,305,368		1,305,368		1,038,006
Weighted average grant date fair value of stock grants per share (in dollars per share) \| $ / shares			$ 5.96		$ 5.96
Unrecognized compensation cost related to unvested restricted stock			$ 5,700,000		$ 5,700,000
Period in which compensation cost expected to be recognized					2 years 1 month 6 days
Potential Performance Shares (PSU)
Operations And Summary Of Significant Accounting Policies [Line Items]
Granted (in shares) \| shares	220,929
Value per share (in dollars per share) \| $ / shares	$ 8.56
Period in which compensation cost expected to be recognized					2 years
Number of performance stock units ("PSUs") outstanding (in shares) \| shares			1,357,417		1,357,417
Weighted average grant date fair value of PSUs per unit (in dollars per share) \| $ / EquityUnit			9.21		9.21
Minimum final number of shares of common stock issuable based on performance multiplier (in shares) \| shares					0
Maximum final number of shares of common stock issuable based on performance multiplier (in shares) \| shares					2,714,834
Unrecognized expense, performance share units					$ 5,000,000.0
General and Administrative Expense
Operations And Summary Of Significant Accounting Policies [Line Items]
Stock-based compensation expense recognized			$ 1,800,000	$ 1,600,000	3,500,000	$ 3,000,000.0
Interest Rate Swap Contracts
Operations And Summary Of Significant Accounting Policies [Line Items]
Outstanding under the bank credit facility			$ 500,000,000.0		$ 500,000,000.0
Interest Rate Swap Contracts \| LIBOR
Operations And Summary Of Significant Accounting Policies [Line Items]
Outstanding bank credit facility percentage					0.33%