Annual report pursuant to Section 13 and 15(d)

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

v3.20.1
The Company and Its Accounting Policies - Additional Information (Detail) - USD ($)
shares in Thousands, $ in Thousands
 12 Months Ended
Apr. 01, 2019
Mar. 31, 2020
Mar. 31, 2019
Mar. 31, 2018
Jun. 24, 2019
Schedule Of Accounting Policies [Line Items]          
Minimum level of likelihood   50.00%      
Description of sale of asset   The sale of the asset (disposal group) is probable, and transfer of the asset (disposal group) is expected to qualify for recognition as a completed sale within one year, except if events or circumstances beyond the Company's control extend the period of time required to sell the asset (disposal group) beyond one year;      
Research and development costs   $ 3,353 $ 3,538 $ 3,211  
Antidilutive securities excluded from computation of earnings per share     39 69  
Interest paid   12 $ 12 $ 12  
Income taxes paid (refunded)   139 (73) 1,916  
Pension and other postretirement benefit adjustments, net of tax   525 348 (1,668)  
Issuance of treasury stock   170 134 130  
Capital expenditures   162 85 0  
Capital leases   0 100 0  
Right-of-use assets   243      
Lease liabilities   235      
Retained earnings   $ 91,389 93,847    
Topic 842 [Member]          
Schedule Of Accounting Policies [Line Items]          
Right-of-use assets $ 677       $ 500
Lease liabilities 732       $ 500
Retained earnings 80        
Decrease in other current assets 47        
Decrease in deferred income tax liability $ 22        
Topic 842 [Member] | Held for Sale [Member]          
Schedule Of Accounting Policies [Line Items]          
Right-of-use assets     500    
Lease liabilities     $ 500    
Retained Earnings [Member]          
Schedule Of Accounting Policies [Line Items]          
Amounts reclassified from accumulated other comprehensive loss to retained earnings       $ 1,828  
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   Jun. 25, 2020      
Maximum [Member] | Topic 842 [Member]          
Schedule Of Accounting Policies [Line Items]          
Lease term   12 months      
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