Employee Benefit Plans - Summary of Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost (Detail) - Supplemental Employee Retirement Plan [Member]	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Weighted-average assumptions used to determine Net Periodic Benefit Cost
Discount rate	4.90%	2.50%
Corridor	10.00%	10.00%
Average future working lifetime	4 years 6 months 7 days	4 years 11 months 26 days
Mortality table	Pri-2012 WC	Pri-2012 WC
Mortality improvement scale	MP-2021	MP-2021

Defined benefit plan assumptions used calculating net periodic benefit cost corridor.

No definition available.

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- Definition

Defined benefit plan weighted average assumptions for determining periodic net benefits costs average future working life time.

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No definition available.

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- Definition

Defined benefit plan weighted average assumptions for determining periodic net benefits costs description of mortality.

+ References

No definition available.

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- Definition

Defined benefit plan weighted average assumptions for determining periodic net benefits costs description of mortality improvement scale.

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No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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