Schedule of Amounts Recognized in Accumulated Other Comprehensive Income (loss) (Detail) - Postretirement Benefit Plans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure
Prior service cost, before tax	$ (40)	$ (49)
Deferred taxes	(1,688)	(1,686)
Total recognized in other comprehensive income (loss), net of tax	$ (1,728)	$ (1,735)

Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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