Schedule of Market Values of Pension Plan Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 127,360	$ 131,685	$ 120,287
Equity Securities U.S. Large Cap
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,306	10,946
Equity Securities U.S. Mid Cap
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,014	3,403
Equity Securities U.S. Small Cap
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,913	3,581
Equity Securities International Developed
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,062	8,315
Equity Securities Emerging Markets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,152	5,631
Fixed Income Securities Core Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	22,904	27,782
Fixed Income Securities Long Duration Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	84,277	68,886
Real Estate REIT Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,474
Cash Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 732	$ 667