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Supplemental Oil and Gas Information (Unaudited) - Schedule of Product Prices Used for Valuing the Reserves (Detail)
12 Months Ended
Dec. 31, 2019
$ / MMBTU
$ / bbl
Dec. 31, 2018
$ / MMBTU
$ / bbl
Dec. 31, 2017
$ / MMBTU
$ / bbl
Oil [Member]      
Supplemental Oil And Gas Reserve Information [Line Items]      
Product prices for reserves 55.69 65.56 51.34
NGL [Member]      
Supplemental Oil And Gas Reserve Information [Line Items]      
Product prices for reserves 55.69 65.56 51.34
Natural Gas [Member]      
Supplemental Oil And Gas Reserve Information [Line Items]      
Product prices for reserves | $ / MMBTU 2.58 3.10 2.98