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Assets Measured at Fair Value on Recurring Basis for Pension Plan (Detail) - Pension Plans - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | $ 137,893 | $ 126,098 | $ 152,006
Mutual Fund |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 127,881 | 114,978 |
Mutual Fund | Equity Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 78,522 | 67,332 |
Mutual Fund | Fixed Income Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 49,359 | 47,646 |
Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 2,266 | 2,598 |
Mutual Fund Including Cash And Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 130,147 | 117,576 |
Real Estate Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 7,746 | 8,522 |
Fair Value, Inputs, Level 1 | Mutual Fund |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 127,881 | 114,978 |
Fair Value, Inputs, Level 1 | Mutual Fund | Equity Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 78,522 | 67,332 |
Fair Value, Inputs, Level 1 | Mutual Fund | Fixed Income Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 49,359 | 47,646 |
Fair Value, Inputs, Level 1 | Cash and Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | 2,266 | 2,598 |
Fair Value, Inputs, Level 1 | Mutual Fund Including Cash And Cash Equivalents |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets measured at fair value | $ 130,147 | $ 117,576 |

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