Components of Net Periodic Benefit Costs (Detail) - Deferred Compensation Plan - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
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Oct. 31, 2015 |
Oct. 31, 2014 |
Oct. 31, 2015 |
Oct. 31, 2014 |
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Amortization of actuarial loss | $ 731 | $ 762 | $ 1,462 | $ 1,525 |
| Interest cost | 703 | 748 | 1,406 | 1,495 |
| Net periodic benefit costs | $ 1,434 | $ 1,510 | $ 2,868 | $ 3,020 |
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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 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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