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Retirement Plans - Defined Benefit Plan, Fair Value of Plan Assets, Unobservable Input Reconciliation (Detail) - Bank and Insurance Investment Contracts [Member] - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |
Fair value of defined benefit plan assets, beginning balance | $ 57,994 | $ 65,945
Net purchases (sales) and appreciation (depreciation) of defined benefit plan assets | 8,197 | (7,951)
Fair value of defined benefit plan assets, ending balance | $ 66,191 | $ 57,994

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- Definition Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan. + References No definition available. + Details
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