Derivative Financial Instruments - Schedule of Notional Amounts and Estimated Fair Values of Commodity Derivative Positions (Detail) bbl in Thousands, MMBTU in Thousands, $ in Thousands	Jun. 30, 2020 USD ($) MMBTU bbl	Dec. 31, 2019 USD ($) bbl MMBTU
Financial Institution Counterparties [Member] | Oil Commodity Derivative [Member]
Derivative Instruments [Line Items]
Oil/Natural Gas Derivative Assets, Notional Amount | bbl	2,512	1,214
Oil/Natural Gas Derivative Liabilities, Notional Amount | bbl	2,054	2,148
Oil/Natural Gas Derivative Assets, Estimated Fair Value	$ 30,220	$ 2,796
Oil/Natural Gas Derivative Liabilities, Estimated Fair Value	$ (7,022)	$ (6,916)
Financial Institution Counterparties [Member] | Natural Gas Commodity Derivative [Member]
Derivative Instruments [Line Items]
Oil/Natural Gas Derivative Assets, Notional Amount | MMBTU	10,414	8,295
Oil/Natural Gas Derivative Liabilities, Notional Amount | MMBTU	10,776	2,689
Oil/Natural Gas Derivative Assets, Estimated Fair Value	$ 2,553	$ 2,131
Oil/Natural Gas Derivative Liabilities, Estimated Fair Value	$ (1,205)	$ (70)
Customer Counterparties [Member] | Oil Commodity Derivative [Member]
Derivative Instruments [Line Items]
Oil/Natural Gas Derivative Assets, Notional Amount | bbl	2,054	2,172
Oil/Natural Gas Derivative Liabilities, Notional Amount | bbl	2,512	1,190
Oil/Natural Gas Derivative Assets, Estimated Fair Value	$ 7,193	$ 7,208
Oil/Natural Gas Derivative Liabilities, Estimated Fair Value	$ (29,916)	$ (2,652)
Customer Counterparties [Member] | Natural Gas Commodity Derivative [Member]
Derivative Instruments [Line Items]
Oil/Natural Gas Derivative Assets, Notional Amount | MMBTU	12,298	2,689
Oil/Natural Gas Derivative Liabilities, Notional Amount | MMBTU	8,891	8,295
Oil/Natural Gas Derivative Assets, Estimated Fair Value	$ 1,358	$ 83
Oil/Natural Gas Derivative Liabilities, Estimated Fair Value	$ (2,417)	$ (2,039)