Retirement Plans - Defined Benefit Pension Plans (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Transition obligation	$ 0	$ 1
Prior service cost	(86)	(141)
Net actuarial loss	1,380	11,333
Amount included in accumulated other comprehensive income (loss)	1,294	11,193
Deferred tax benefit	(382)	(3,309)
Amount included in accumulated other comprehensive income (loss), net of tax	$ 912	$ 7,884

Defined Benefit Plan Accumulated Other Comprehensive Income Deferred Income Tax

No definition available.

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- Definition

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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- Definition

Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for transition asset (obligation) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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