Employee Benefit Plans - Components of Postretirement Benefit Expense (Income) and Pension (Benefit) Cost (Detail) - Other Postretirement Benefit Plans [Member] - USD ($) $ in Thousands |
12 Months Ended | ||
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Mar. 31, 2018 |
Mar. 31, 2017 |
Mar. 31, 2016 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Interest cost on accumulated benefit obligation | $ 26 | $ 26 | $ 29 |
| Amortization of actuarial loss | 37 | 36 | 40 |
| Net pension cost (benefit) | $ 63 | $ 62 | $ 69 |
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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/presentationRef
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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 cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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