Annual report pursuant to Section 13 and 15(d)

Changes in Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Detail)

v3.20.1
Changes in Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Detail) - USD ($)
$ in Thousands
12 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning balance $ 98,966 $ 103,349 $ 114,110
Other comprehensive loss before reclassifications (1,494) (1,316)  
Amounts reclassified from accumulated other comprehensive loss 771 733  
Total other comprehensive (loss) income (723) (583) 2,012
Ending Balance 96,724 98,966 103,349
Pension and Other Postretirement Benefits Items [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning balance (8,947) (8,599)  
Other comprehensive loss before reclassifications (1,296) (1,081)  
Amounts reclassified from accumulated other comprehensive loss 771 733  
Total other comprehensive (loss) income (525) (348)  
Ending Balance (9,472) (8,947) (8,599)
Foreign Currency Items [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning balance 114 349  
Other comprehensive loss before reclassifications (198) (235)  
Total other comprehensive (loss) income (198) (235)  
Ending Balance (84) 114 349
Accumulated Other Comprehensive Loss [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning balance (8,833) (8,250) (8,434)
Ending Balance $ (9,556) $ (8,833) $ (8,250)