Condensed Consolidated Statements of Income (Loss) (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Nov. 30, 2014	Nov. 30, 2013
Income Statement [Abstract]
Sales	$ 103,636us-gaap_SalesRevenueGoodsNet	$ 109,251us-gaap_SalesRevenueGoodsNet
Cost of sales	85,490us-gaap_CostOfGoodsSold	98,542us-gaap_CostOfGoodsSold
Gross margin	18,146us-gaap_GrossProfit	10,709us-gaap_GrossProfit
Operating expenses	12,108	7,801
Research and development expenses	1,628us-gaap_ResearchAndDevelopmentExpense	1,267us-gaap_ResearchAndDevelopmentExpense
Income from operations	4,410us-gaap_OperatingIncomeLoss	1,641us-gaap_OperatingIncomeLoss
Interest expense	(904)us-gaap_InterestExpense	(813)us-gaap_InterestExpense
Other non-operating (expense) income, net	(72)us-gaap_OtherNonoperatingIncomeExpense	8us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	3,434	836
Income tax expense	1,300us-gaap_IncomeTaxExpenseBenefit	348us-gaap_IncomeTaxExpenseBenefit
Net income (loss)	$ 2,134us-gaap_NetIncomeLoss	$ 488us-gaap_NetIncomeLoss
Weighted-average common shares and equivalents outstanding:
Basic	12,583	12,473
Diluted	13,040	12,841
Earnings per common share:
Basic earnings per share	$ 0.17us-gaap_EarningsPerShareBasic	$ 0.04us-gaap_EarningsPerShareBasic
Diluted earnings per share	$ 0.16us-gaap_EarningsPerShareDiluted	$ 0.04us-gaap_EarningsPerShareDiluted
Dividends declared per common share	$ 0	$ 0

Operating expenses before research and development.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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