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Employee Benefit Plans - Fair Values of Company's Pension Plan Assets by Asset Category (Detail) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Thousands | Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 29,826 | $ 31,438 | $ 32,753
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 29,826 | 31,438 |
Cash [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 238 | 81 |
Cash [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 238 | 81 |
U.S. companies, Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4,033 | 4,141 |
U.S. companies, Equity Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4,033 | 4,141 |
International companies, Equity Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,549 | 2,610 |
International companies, Equity Securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 2,549 | 2,610 |
Fixed income, Corporate bond funds, Long-term [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 23,006 | 24,606 |
Fixed income, Corporate bond funds, Long-term [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 23,006 | $ 24,606 |

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