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Employee Benefit Plans (Pension Benefit Plan) - Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Compensation And Retirement Disclosure [Abstract]
Net actuarial loss	$ (13,545)	$ (12,973)

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- Definition

Defined benefit plan accumulated other comprehensive income net actuarial gains losses net of tax.

+ References

No definition available.

+ Details

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Period Type:	instant

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- References

No definition available.

+ Details

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