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The Company and Its Accounting Policies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Mar. 31, 2014 | Mar. 31, 2013 | Mar. 31, 2012
Schedule Of Accounting Policies [Line Items] |  |  |
Company recognizes planned manufacturing process | 28 days |  |
Direct labor hours worked on contracts | 0 days 575 hours |  |
Minimum level of likelihood | 50.00% |  |
Research and development costs | $ 3,436 | $ 3,579 | $ 3,197
Antidilutive securities excluded from computation of earnings per share | 2 | 14 | 14
Interest paid | 12 | 59 | 100
Income taxes paid | 3,302 | 4,064 | 8,111
Pension and other postretirement benefit adjustments, net of tax | (2,275) | (92) | 3,223
Issuance of treasury stock | 317 | 297 | 330
Capital expenditures | 40 | 142 | 13
Capital leases | $ 90 | $ 11 | $ 205
Buildings and Leasehold Improvements [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Estimated useful lives range | 40 years |  |
Backlog [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Estimated useful lives | 6 months |  |
Customer Relationships [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Estimated useful lives | 15 years |  |
Minimum [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Substantial completion of manufacturing process | 95.00% |  |
Treasury with original maturities period | 3 months |  |
Minimum [Member] | Office Equipment [Member] |  |  |
Schedule Of Accounting Policies [Line Items] |  |  |
Estimated useful lives range | 5 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] |  |  |
Investment maturity date range end | Oct. 03, 2014 |  |
Treasury with original maturities period | 1 year |  |
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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