Exit and Termination Costs - Summary of Exit and Termination Costs (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Restructuring Cost And Reserve [Line Items]
Severance costs	$ 0	$ (148)	$ 509	$ 1,447
Total termination costs	(15,946)	10,297	(2,232)	11,892
Pennsylvania
Restructuring Cost And Reserve [Line Items]
Exit cost	184	10,445	394	10,445
North Louisiana Contract Release
Restructuring Cost And Reserve [Line Items]
Exit cost	$ (16,130)	$ 0	$ (3,135)	$ 0