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The Company and Its Accounting Policies - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jun. 01, 2021 | Mar. 31, 2023 | Mar. 31, 2022 | Mar. 31, 2021
Schedule Of Accounting Policies [Line Items] |  |  |  |
Minimum level of likelihood |  | 50.00% |  |
Research and development costs |  | $ 4,144 | $ 3,845 | $ 3,367
Antidilutive securities excluded from computation of earnings per share |  |  | 33 | 37
Interest paid |  | 1,026 | $ 417 | $ 11
Income taxes paid (refunded) |  | 185 | 2,012 | 200
Pension and other post retirement income (loss) adjustments, net of income tax |  | (500) | 728 | 1,774
Issuance of treasury stock |  | 279 | 9,167 | 222
Capital expenditures |  | 483 | 177 | 173
Acquisition of Barber-Nichols, LLC |  | 0 | 60,282 | 0
Employee Stock Purchase Plan [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Issuance of treasury stock |  | $ 279 | $ 204 | $ 222
Barber Nichols Inc [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Payments to Acquire Businesses, Gross | $ 61,150 |  |  |
Buildings and Leasehold Improvements [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Estimated useful lives range |  | 40 years |  |
Minimum [Member] | Office Equipment [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Estimated useful lives range |  | 3 years |  |
Minimum [Member] | Manufacturing Equipment [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Estimated useful lives range |  | 8 years |  |
Maximum [Member] | Office Equipment [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Estimated useful lives range |  | 8 years |  |
Maximum [Member] | Manufacturing Equipment [Member] |  |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |  |
Estimated useful lives range |  | 25 years |  |

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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257 + Details
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