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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Summary of Changes in Reserve for Future Abandonment Costs (Detail) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]    
Reserve for future abandonment costs at beginning of period $ 19,290 $ 18,151
New wells placed on production 862 289
Liabilities settled and assets disposed of (6) (27)
Accretion expense 602 581
Reserve for future abandonment costs at end of period $ 20,748 $ 18,994