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Revenue Recognition - Revenue Disaggregated by Product Line and Geographic Area (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Mar. 31, 2022
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | $ 185,533 | $ 157,118 | $ 122,814
Asia [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 15,144 | 16,040 | 13,687
Canada [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 4,229 | 4,464 | 3,583
Middle East [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 2,568 | 2,914 | 2,489
South America [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 733 | 3,021 | 1,972
U.S. [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 155,908 | 127,519 | 97,718
All Other [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 6,951 | 3,160 | 3,365
Refining [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 29,087 | 27,270 | 24,406
Chemical/Petrochemical [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 20,893 | 21,950 | 15,955
Defense [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 99,493 | 65,327 | 62,189
Space [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | 13,282 | 21,180 | 5,744
Other Commercial [Member] |  |  |
Disaggregation Of Revenue [Line Items] |  |  |
Net sales | $ 22,778 | $ 21,391 | $ 14,520

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