Employee Benefit Plans - Components of Net Periodic Defined Benefit Cost (Income) (Detail) - Defined Benefit Pension Plans - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 279	$ 355	$ 711	$ 1,065
Expected return on plan assets	(398)	(461)	(1,194)	(1,383)
Recognized actuarial losses	376	380	1,128	1,140
Total	$ 257	$ 274	$ 645	$ 822