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Changes in Accumulated Other Comprehensive Loss - Reclassifications Out of Accumulated Other Comprehensive Loss by Component (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Income before provision for income taxes | $ 39 | $ (15,158) | $ 5,069 | $ (13,851)
Provision for income taxes | (56) | (3,536) | 824 | (3,174)
Net income | 95 | (11,622) | 4,245 | (10,677)
Reclassifications Out of Accumulated Other Comprehensive Loss [Member] | Amortization of Actuarial Loss [Member] |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Income before provision for income taxes | (218) | (262) | (655) | (788)
Reclassifications Out of Accumulated Other Comprehensive Loss [Member] | Pension and Other Postretirement Benefits Items [Member] |  |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |
Provision for income taxes | (48) | 17 | (145) | (169)
Net income | $ (170) | $ (279) | $ (510) | $ (619)

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