Annual report pursuant to Section 13 and 15(d)

The Company and Its Accounting Policies - Additional Information (Detail)

v3.7.0.1
The Company and Its Accounting Policies - Additional Information (Detail) - USD ($)
shares in Thousands, $ in Thousands
 12 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Mar. 31, 2015
Schedule Of Accounting Policies [Line Items]      
Company recognizes planned manufacturing process 28 days    
Direct labor hours worked on contracts 575 hours    
Receivables billed but not paid under retainage provisions in its customer contracts $ 971 $ 2,071  
Substantial completion of manufacturing process 95.00%    
Minimum level of likelihood 50.00%    
Research and development costs $ 3,863 $ 3,746 $ 3,585
Antidilutive securities excluded from computation of earnings per share 11 54 12
Interest paid $ 10 $ 10 $ 11
Income taxes paid 951 5,423 6,491
Pension and other postretirement benefit adjustments, net of tax (2,493) 1,470 3,294
Issuance of treasury stock 241 255 325
Capital expenditures 4 53 174
Capital leases $ 95 $ 126 $ 22
Customer Relationships [Member]      
Schedule Of Accounting Policies [Line Items]      
Estimated useful lives 15 years    
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 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]      
Treasury with original maturities period 1 year    
Investment maturity date range end Feb. 15, 2018    
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