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Summary of Significant Accounting Policies - Additional Information 1 (Detail) - USD ($)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Accounting Policies [Abstract]      
Impairment of oil and gas properties $ 0 $ 0  
Goodwill $ 335,897,000   $ 335,897,000