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Debt to total earnings before interest taxes depreciation or depletion amortization and exploration expense.

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Extended the date of certain minimum hedging requirements description.

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To extend the dates for certain requirements that will be due under the credit agreement.

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LIBOR rate interest period.

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Pledge and security interest percentage of equity interests pledged.

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The cash inflow from a decommissioning trust fund.

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Secured by percentage of mortgages.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Credit Facility - Additional Information (Detail) - USD ($)							4 Months Ended	8 Months Ended	12 Months Ended
	Jun. 24, 2019	Dec. 21, 2018	Nov. 20, 2018	Nov. 02, 2018	Oct. 05, 2018	May 04, 2017	May 04, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Nov. 08, 2019	Nov. 07, 2019	Aug. 06, 2019	Aug. 05, 2019
Line Of Credit Facility [Line Items]
Proceeds from Beta Decommissioning Trust account	$ 90,000,000		$ 1,000,000		$ 61,500,000
Gain (loss) on extinguishment of debt				$ 3,000,000				$ 0	$ 0	$ (3,034,000)
Repayment of predecessor's revolving credit facility								$ 63,000,000	134,000,000	$ 397,000,000
Letters of credit outstanding									1,700,000
Predecessor [Member]
Line Of Credit Facility [Line Items]
Gain (loss) on extinguishment of debt							$ 0
Repayment of predecessor's revolving credit facility							$ 98,252,000
Predecessor $2.0 billion revolving credit facility, variable-rate, due March 2018 [Member]
Line Of Credit Facility [Line Items]
Revolving credit facility, maximum borrowing capacity									2,000,000,000
Predecessor $2.0 billion revolving credit facility, variable-rate, due March 2018 [Member] \| Predecessor [Member]
Line Of Credit Facility [Line Items]
Repayment of predecessor's revolving credit facility						$ 24,800,000
New Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Extended hedging requirements		Extend the date by which OLLC was required to show compliance with certain minimum hedging requirements set forth in the New Credit Agreement from December 31, 2018 to February 28, 2019
Extended date after the closing date		60 days
Credit Facility [Member]
Line Of Credit Facility [Line Items]
Borrowing base									$ 450,000,000		$ 450,000,000	$ 530,000,000	$ 530,000,000	$ 425,000,000
Maturity date									Nov. 02, 2023
LIBOR rate interest period				1 month
Credit Facility [Member] \| Amplify Acquisitionco Inc
Line Of Credit Facility [Line Items]
Pledge and security interest				100.00%
Credit Facility [Member] \| Minimum [Member]
Line Of Credit Facility [Line Items]
Current ratio				1.00%
Credit Facility [Member] \| Minimum [Member] \| Oil and Gas Properties [Member]
Line Of Credit Facility [Line Items]
Secured by percentage of mortgages				85.00%
Credit Facility [Member] \| Minimum [Member] \| Proved Developed and Producing Oil and Gas Properties [Member]
Line Of Credit Facility [Line Items]
Secured by percentage of mortgages				85.00%
Credit Facility [Member] \| Maximum [Member]
Line Of Credit Facility [Line Items]
Total debt to EBITDAX				4.00%
Credit Facility [Member] \| Federal Funds Effective Rate [Member]
Line Of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate				0.50%
Credit Facility [Member] \| LIBOR [Member]
Line Of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate				1.00%
Credit Facility [Member] \| LIBOR [Member] \| Minimum [Member]
Line Of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate				2.00%
Credit Facility [Member] \| LIBOR [Member] \| Maximum [Member]
Line Of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate				3.00%
Credit Facility [Member] \| Base Rate [Member] \| Minimum [Member]
Line Of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate				1.00%
Credit Facility [Member] \| Base Rate [Member] \| Maximum [Member]
Line Of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate				2.00%
Credit Facility
Line Of Credit Facility [Line Items]
Gain (loss) on extinguishment of debt				$ 3,000,000