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Retirement Plans and Other Post-Retirement Benefits - Other Changes in Plan Assets and Benefit Obligations (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Actuarial (gain) loss		$ (203)	$ 1,750
Recognized prior service costs		(48)	(48)
Amortization of actuarial (gain) loss	$ (790)	(790)	(655)	$ (2,759)
Total recognized in other comprehensive (income) loss		(1,041)	1,047
Total recognized in net periodic benefit cost and other comprehensive loss		771	2,960
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Actuarial (gain) loss		79	883
Amortization of actuarial (gain) loss	$ (47)	(47)	834	$ 892
Total recognized in other comprehensive (income) loss		32	1,717
Total recognized in net periodic benefit cost and other comprehensive loss		$ 2	$ 609

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