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Components of Net Periodic Benefit Costs (Detail) (Deferred Compensation Plan, USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
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Apr. 30, 2013
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Apr. 30, 2012
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Apr. 30, 2011
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Deferred Compensation Plan
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Service cost | $ 137 | ||
| Interest cost | 2,868 | 3,346 | 3,495 |
| Amortization of actuarial loss | 2,357 | 1,374 | 422 |
| Net periodic benefit cost | $ 5,225 | $ 4,720 | $ 4,054 |
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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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- Details
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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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- Definition
The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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