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The Company and Its Accounting Policies - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2019
Schedule Of Accounting Policies [Line Items] |  |  |
Minimum level of likelihood | 50.00% |  |
Research and development costs | $ 3,367 | $ 3,353 | $ 3,538
Antidilutive securities excluded from computation of earnings per share | 37 |  | 39
Interest paid | $ 11 | 12 | $ 12
Income taxes paid (refunded) | 200 | 139 | (73)
Pension and other postretirement benefit income (loss) adjustments, net of tax | 1,774 | (525) | (348)
Issuance of treasury stock | 222 | 170 | 134
Capital expenditures | 173 | 162 | 85
Capital leases | $ 0 | $ 0 | $ 100
Buildings and Leasehold Improvements [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Estimated useful lives range | 40 years |  |
Minimum [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Treasury with original maturities period | 3 months |  |
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] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Treasury with original maturities period | 1 year |  |
Investment maturity date range end | Jun. 24, 2021 |  |
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 http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 + Details
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