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Employee Benefit Plans (Pension Benefit Plan) - Schedule of Cash Equivalents and Investments Held at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 32,762	$ 32,263	$ 28,016
Pension Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32,762	32,263
Pension Benefit Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	801	1,935
Pension Benefit Plan [Member] | Available-For-Sale Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31,961	30,328
Pension Benefit Plan [Member] | Corporate Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,528	6,746
Pension Benefit Plan [Member] | Government Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,721	5,971
Pension Benefit Plan [Member] | Emerging Markets Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		307
Pension Benefit Plan [Member] | Global Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,170	11,638
Pension Benefit Plan [Member] | Balanced Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,919	2,515
Pension Benefit Plan [Member] | Emerging Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,259	1,848
Pension Benefit Plan [Member] | Large Cap Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	235	198
Pension Benefit Plan [Member] | Global Real Estate Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,129	799
Pension Benefit Plan [Member] | Managed Futures Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		306
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	32,762	32,263
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	801	1,935
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Available-For-Sale Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31,961	30,328
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7,528	6,746
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Government Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,721	5,971
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emerging Markets Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		307
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Global Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,170	11,638
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Balanced Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,919	2,515
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Emerging Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,259	1,848
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Large Cap Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	235	198
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Global Real Estate Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,129	799
Pension Benefit Plan [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Managed Futures Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 306

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+ References

No definition available.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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-Publisher FASB
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