Employee Benefit Plans - Components of Postretirement Benefit Cost (Income) and Pension Cost (Benefit) (Detail) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Thousands |
12 Months Ended | ||
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Mar. 31, 2019 |
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Service cost during the period | $ 571 | $ 598 | $ 600 |
| Interest cost on projected benefit obligation | 1,339 | 1,423 | 1,450 |
| Expected return on assets | (3,062) | (2,977) | (2,873) |
| Actuarial loss | 847 | 1,013 | 1,351 |
| Net pension (benefit) cost and postretirement benefit expense | $ (305) | $ 57 | $ 528 |
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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