Condensed Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Feb. 28, 2014
Revenues	$ 34,427us-gaap_Revenues	$ 30,922us-gaap_Revenues	$ 67,661us-gaap_Revenues	$ 61,957us-gaap_Revenues
Cost of revenues	23,795us-gaap_CostOfRevenue	22,412us-gaap_CostOfRevenue	47,584us-gaap_CostOfRevenue	44,541us-gaap_CostOfRevenue
Gross margin	10,632us-gaap_GrossProfit	8,510us-gaap_GrossProfit	20,077us-gaap_GrossProfit	17,416us-gaap_GrossProfit
Operating expenses:
Selling, general and administrative expenses	8,778	8,027	17,532	15,806
Income from operations	1,854us-gaap_OperatingIncomeLoss	483us-gaap_OperatingIncomeLoss	2,545us-gaap_OperatingIncomeLoss	1,610us-gaap_OperatingIncomeLoss
Other (expense) income:
Net loss on trading securities	(13)	(148)	(56)	(57)
Gain on sale of property	0	0	0	535
Interest and other income (expense)	6us-gaap_InterestIncomeExpenseNet	(112)us-gaap_InterestIncomeExpenseNet	6us-gaap_InterestIncomeExpenseNet	(211)us-gaap_InterestIncomeExpenseNet
Other (expense) income, net	(7)us-gaap_NonoperatingIncomeExpense	(260)us-gaap_NonoperatingIncomeExpense	(50)us-gaap_NonoperatingIncomeExpense	267us-gaap_NonoperatingIncomeExpense
Income before income taxes	1,847	223	2,495	1,877
Provision for income taxes	728us-gaap_IncomeTaxExpenseBenefit	114us-gaap_IncomeTaxExpenseBenefit	981us-gaap_IncomeTaxExpenseBenefit	704us-gaap_IncomeTaxExpenseBenefit
Net income	1,119us-gaap_NetIncomeLoss	109us-gaap_NetIncomeLoss	1,514us-gaap_NetIncomeLoss	1,173us-gaap_NetIncomeLoss
Cumulative preferred stock dividend	(19)	(19)	(38)	(38)
Net income attributable to common shareholders	$ 1,100	$ 90	$ 1,476	$ 1,135
Basic and diluted earnings per share (in dollars per share)	$ 0.23us-gaap_EarningsPerShareBasicAndDiluted	$ 0.02us-gaap_EarningsPerShareBasicAndDiluted	$ 0.30us-gaap_EarningsPerShareBasicAndDiluted	$ 0.23us-gaap_EarningsPerShareBasicAndDiluted
Basic and diluted weighted average common shares outstanding (in shares)	4,861,590	4,861,590	4,861,590	4,861,590

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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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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The net amount of operating interest income (expense).

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The amount of preferred stock dividends that is an adjustment to net income apportioned to common stockholders.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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