Benefit Plans - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Compensation And Retirement Disclosure [Abstract]
Service cost	$ 568,000	$ 554,000
Periodic pension income	700,000
Minimum required pension plan contribution	5,000,000.0
Available credit balance	60,900,000
Expected voluntary contribution for the year 2020	$ 0

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount of contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

+ References

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-Publisher FASB
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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- Definition

Defined benefit plan, periodic pension income.

+ References

No definition available.

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- Definition

Amount of voluntary contributions received and expected to be received by defined benefit plan from employer in current fiscal year.

+ References

No definition available.

+ Details

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