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Stock Compensation Plans - Summary of Issuance of Shares, Stock-Based Compensation Cost and Related Tax Benefits (Detail) - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023 | Mar. 31, 2022
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Stock based compensation cost | $ 1,188 | $ 785 | $ 780
Related tax benefits | $ 264 | $ 173 | $ 173
Employee Stock Purchase Plan [Member] |  |  |
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] |  |  |
Issued from treasury shares | 0 | 29 | 18
Issued from common stock | 50 | 17 | 0
Stock based compensation cost | $ 91 | $ 21 | $ 29
Related tax benefits | $ 20 | $ 5 | $ 7

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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479830/718-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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