Summary of Significant Accounting Policies - Summary of Carrying Amounts and Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Derivative financial instruments	$ 4,627	$ 8,913
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative financial instruments	60,820	47,005
Bank Credit Facility
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term debt, Carrying Value	550,000	500,000
Long-term debt, Fair Value	550,000	500,000
Level 1 \| 7.5% Senior Notes due 2025
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term debt, Carrying Value	189,304	473,728
Long-term debt, Fair Value	253,565	628,691
Level 1 \| 9.75% Senior Notes due 2026
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term debt, Carrying Value	844,068	1,577,824
Long-term debt, Fair Value	951,498	1,769,625
Level 1 \| 6.75% Senior Notes due 2029:
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Long-term debt, Carrying Value	1,257,443	0
Long-term debt, Fair Value	1,275,000	0
Derivative Financial Instruments \| Level 2 and Level 3
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Derivative financial instruments	8,151	9,574
Derivative financial asset, Fair value	8,151	9,574
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative financial instruments	61,018	49,369
Derivative financial liabilities, Fair value	$ 61,018	$ 49,369

Fair value of liability associated with financial asset or other 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.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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