Supplemental Information on Natural Gas and Oil Exploration, Development and Production Activities (Unaudited) - Costs Incurred for Property Acquisition, Exploration and Development (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Acquisitions
Acreage purchases	[1]	$ 21,942	$ 26,166	$ 57,324
Development	[1]	381,753	369,093	666,984
Exploration:
Exploration drilling costs incurred	[1]	6,329	7,709	0
Gas gathering facilities:
Development	[1]	3,402	3,694	3,583
Subtotal	[1]	436,981	439,317	764,574
Asset retirement obligations	[1]	18,634	2,610	11,193
Total costs incurred	[1]	455,615	441,927	775,767
Exploration Expense
Exploration:
Exploration costs incurred	[1]	22,048	31,376	35,117
Stock-based compensation expense	[1]	$ 1,507	$ 1,279	$ 1,566

[1] Includes cost incurred whether capitalized or expensed.