Pension Information - Components of Net Periodic Pension Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Compensation And Retirement Disclosure [Abstract]
Service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	95	121	190	242
Expected return on plan assets	(160)	(187)	(320)	(374)
Other components	81	72	163	145
Net periodic pension cost	$ 16	$ 6	$ 33	$ 13