Commitments And Contingencies (Schedule Of Minimum Rental Requirements)(Details) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2013
Commitments And Contingencies [Abstract]
2014	$ 3,411
2015	3,102
2016	2,768
2017	1,336
2018	217
2019 (and thereafter)	92
Total, Operating	10,926
Capital Leases, Future Minimum Payments, Net Present Value [Abstract]
2014	997
2015	997
2016	986
2017	866
2018	678
2019 (and thereafter)	4,140
Total, Capital	8,664
Less amounts representing interest (2%)	(925)
Total obligations under capital leases	$ 7,739

Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the forth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the second fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing after the fifth fiscal year following the latest fiscal year for capital leases.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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