Deferred Compensation And Retirement Plans (Expected Benefit Payments Associated With Future Service) (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2013
Deferred Compensation Plan
Defined Benefit Plan Disclosure [Line Items]
2014	$ 6,602
2015	6,515
2016	6,789
2017	6,520
2018	6,184
2019-2023	30,853
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2014	313
2015	319
2016	320
2017	316
2018	274
2019-2023	$ 1,335

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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