XML 101 R90.htm IDEA: XBRL DOCUMENT v3.21.2
Costs Incurred for Property Acquisition, Exploration and Development (Detail) - USD ($)
$ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Acquisitions:      
Acreage purchases $ 14,014   $ 26,166
Development 298,300   369,093
Gas gathering facilities:      
Development 2,846   3,694
Subtotal 337,906   439,317
Asset retirement obligations 2,879 $ 4,587 2,610
Total costs incurred 340,785   441,927
Exploration Expense      
Exploration:      
Drilling 6,299   7,709
Expense 15,331   31,376
Stock-based compensation expense $ 1,116   $ 1,279