Debt and Leases Debt (Details) (USD $) In Thousands, unless otherwise specified	Apr. 30, 2013
Debt Instrument [Line Items]
Debt and Capital Leases, minimum payment due in less than 12 months	$ 410
Debt and Capital Leases, Future Minimum Payments, Due in Two Years	331
Debt and Capital Leases, Future Minimum Payments, Due in Three Years	286
Debt and Capital Leases, Future Minimum Payments, Due in Four Years	233
Debt and Capital Leases, Future Minimum Payments, Due in Five Years	245
Debt and Capital Leases, Future Minimum Payments, Due Thereafter	5,749
Debt and Capital Leases, Future Minimum Payments Due	$ 7,254

Debt and Capital Leases, Future Minimum Payments Due

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Debt and Capital Leases, Future Minimum Payments, Due in Five Years

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Debt and Capital Leases, Future Minimum Payments, Due in Four Years

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Debt and Capital Leases, Future Minimum Payments, Due in Three Years

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Debt and Capital Leases, Future Minimum Payments, Due in Two Years

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Debt and Capital Leases, Future Minimum Payments, Due Thereafter

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Debt and Capital Leases minimum payment due in less than 12 months

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