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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information 1 (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
Accounting Policies [Abstract]          
Impairment of oil and gas properties $ 0 $ 0 $ 0 $ 0  
Goodwill $ 335,897,000   $ 335,897,000   $ 335,897,000