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, 2017 |
Mar. 31, 2016 |
Mar. 31, 2015 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Interest cost on projected benefit obligation | $ 26 | $ 29 | $ 31 |
| Unrecognized prior service cost | (106) | ||
| Actuarial loss | 36 | 40 | 35 |
| Net pension cost (benefit) | $ 62 | $ 69 | $ (40) |
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- Definition The amount of gains or losses recognized in net periodic benefit cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation. 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 The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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