Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Jul. 31, 2014
Debt Instrument [Line Items]
Bank Term Loan under Credit Agreement	$ 25,000us-gaap_LoansPayableToBank	$ 48,125us-gaap_LoansPayableToBank
Seller Financing-Promissory Notes		18,000us-gaap_NotesPayable
Total	28,588us-gaap_LongTermDebt	69,966us-gaap_LongTermDebt
Less: financing fees	(1,072)	(1,218)
Less: current portion	(1,579)us-gaap_LongTermDebtCurrent	(3,831)us-gaap_LongTermDebtCurrent
Total long-term debt	25,937us-gaap_LongTermDebtNoncurrent	64,917us-gaap_LongTermDebtNoncurrent
Total debt	28,588us-gaap_LongTermDebt	69,966us-gaap_LongTermDebt
Bank Term Loan-Commerzbank
Debt Instrument [Line Items]
Bank Term Loan under Credit Agreement	$ 3,588	$ 3,841

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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