Employee Benefit Plans - Net Periodic Pension Cost (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 710	$ 758	$ 1,413	$ 1,508
Interest cost	1,222	1,031	2,430	2,051
Expected return on plan assets	(3,229)	(2,957)	(6,422)	(5,881)
Recognized net actuarial loss	832	1,589	1,656	3,161
Net periodic pension cost	$ (465)	$ 421	$ (923)	$ 839
Weighted-average assumptions:
Discount rate	3.08%	2.81%	3.08%	2.81%
Expected return on assets	6.25%	6.25%	6.25%	6.25%
Prior to Age 40 [Member]
Weighted-average assumptions:
Rate of compensation increase	5.00%	5.00%	5.00%	5.00%
Ages 40-54 [Member]
Weighted-average assumptions:
Rate of compensation increase	4.00%	4.00%	4.00%	4.00%
Otherwise [Member]
Weighted-average assumptions:
Rate of compensation increase	3.50%	3.50%	3.50%	3.50%

Assumption of the interest rate used to bring future cash flows to the present to account for the time value of money.

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Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of 10 percent of greater of fair value of plan assets or benefit obligation.

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Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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