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v3.20.1

Changes in Accumulated Other Comprehensive Loss - Reclassifications Out of Accumulated Other Comprehensive Loss by Component (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income before provision for income taxes |  |  |  |  |  |  |  |  | $ 2,312 | $ (145) | $ (12,854)
Provision for income taxes |  |  |  |  |  |  |  |  | 440 | 163 | (3,010)
Net income | $ 576 | $ 9 | $ 1,205 | $ 82 | $ (4,553) | $ 95 | $ 1,827 | $ 2,323 | 1,872 | (308) | $ (9,844)
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 |  |  |  |  |  |  |  |  | (997) | (875) |
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] |  |  |  |  |  |  |  |  |  |  |
Income before provision for income taxes |  |  |  |  |  |  |  |  | (997) | (875) |
Provision for income taxes |  |  |  |  |  |  |  |  | (226) | (142) |
Net income |  |  |  |  |  |  |  |  | $ (771) | $ (733) |

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