Debt - Long-term Debt and Capital Lease Obligations Current and Non Current (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Debt Instrument [Line Items]
Capital lease obligations	$ 231	$ 423
Debt and capital lease obligations, including current portion and short-term borrowings	72,970	84,462
Less: current portion and short-term borrowings	231	458
Long-term debt and capital lease obligations	72,739	84,004
Secured Debt [Member]
Debt Instrument [Line Items]
Carrying amount of debt	71,506	82,606
Iowa Department of Economic Development Loans [Member]
Debt Instrument [Line Items]
Carrying amount of debt	$ 1,233	$ 1,433

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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