Quarterly report [Sections 13 or 15(d)]

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

v3.26.3
Changes in Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Sep. 30, 2026
Jun. 30, 2026
Sep. 30, 2025
Jun. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Accumulated Other Comprehensive Income (Loss) [Line Items]            
Beginning balance $ 192,196 $ 140,315 $ 123,384 $ 119,577 $ 140,315 $ 119,577
Other comprehensive income (loss) before reclassifications 37 61 (56) 50    
Amounts reclassified from accumulated other comprehensive loss 132 132 161 162    
Total other comprehensive income (loss) 169 193 105 212 362 317
Ending Balance 198,301 192,196 127,590 123,384 198,301 127,590
Pension and Other Postretirement Benefits Items [Member]            
Accumulated Other Comprehensive Income (Loss) [Line Items]            
Beginning balance (5,452) (5,584) (6,509) (6,671) (5,584) (6,671)
Other comprehensive income (loss) before reclassifications 0 0 0 0    
Amounts reclassified from accumulated other comprehensive loss 132 132 161 162    
Total other comprehensive income (loss) 132 132 161 162    
Ending Balance (5,320) (5,452) (6,348) (6,509) (5,320) (6,348)
Foreign Currency Items [Member]            
Accumulated Other Comprehensive Income (Loss) [Line Items]            
Beginning balance (204) (265) (266) (316) (265) (316)
Other comprehensive income (loss) before reclassifications 37 61 (56) 50    
Amounts reclassified from accumulated other comprehensive loss 0 0 0 0    
Total other comprehensive income (loss) 37 61 (56) 50    
Ending Balance (167) (204) (322) (266) (167) (322)
Accumulated Other Comprehensive Loss [Member]            
Accumulated Other Comprehensive Income (Loss) [Line Items]            
Beginning balance (5,656) (5,849) (6,775) (6,987) (5,849) (6,987)
Ending Balance $ (5,487) $ (5,656) $ (6,670) $ (6,775) $ (5,487) $ (6,670)