Capitalized Costs and Accumulated Depreciation, Depletion and Amortization (Detail) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Natural gas properties:
Properties subject to depletion	[1]	$ 10,312,071	$ 9,855,287
Unproved properties	[1]	778,430	800,592
Total	[1]	11,090,501	10,655,879
Accumulated depletion and depreciation	[1]	(5,019,169)	(4,765,475)
Natural gas and oil properties, successful efforts method, net	[1]	$ 6,071,332	$ 5,890,404

[1] Includes capitalized asset retirement costs and the associated accumulated amortization.