Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Revenue	$ 231,849	$ 214,401	$ 562,118	$ 460,607
Cost of sales	174,809	160,195	425,423	341,705
Gross profit	57,040	54,206	136,695	118,902
Selling, general, and administrative expenses	41,049	41,652	117,701	109,609
Income from operations	15,991	12,554	18,994	9,293
Interest expense	1,141	1,051	3,540	3,138
Income before income taxes	14,850	11,503	15,454	6,155
Net income	$ 14,850	$ 11,503	$ 15,454	$ 6,155
Basic net income per common share	$ 0.60	$ 0.48	$ 0.63	$ 0.26
Diluted net income per common share	$ 0.59	$ 0.47	$ 0.61	$ 0.25
Weighted average number of common shares used in computing net income per common share:
Basic	24,654,076	24,012,991	24,491,338	23,857,606
Diluted	25,316,092	24,719,369	25,175,538	24,601,712

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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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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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The net result for the period of deducting operating expenses from operating revenues.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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