Retirement Plans - Components of Net Periodic Benefit Cost for Domestic Retirement Plans (Detail) - United States - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1,420	$ 1,858
Recognized net actuarial loss	872	1,065
Net periodic benefit cost	$ 2,292	$ 2,923
Discount rate	2.75%	4.00%

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average rate for present value of future retirement benefits cash flows, 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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No definition available.

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- Definition

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

+ References

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

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