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Percentage of market price of one share of common stock on offering date that participants pay for shares.

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No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of share options (or share units) exercised during the current period.

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Note 4 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended			9 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allocated Share-based Compensation Expense	$ 590,419		$ 370,465	$ 1,774,330	$ 843,658
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	5,750,033			$ 5,750,033
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				7 years 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				15,850	172,450
Proceeds from Stock Options Exercised				$ 28,718	$ 473,651
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term				3 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 405,657			$ 405,657
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Market Price Percentage, Offering Date				85.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans		11,144		14,723
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price		$ 15.21		$ 11.22
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	117,255			117,255
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				3,795
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 16.45
Restricted Stock [Member] \| Employee and Non-Employee Directors [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				1 year	1 year
Restricted Stock [Member] \| Non Employee Directors [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				3,795	2,712
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 16.45	$ 14.73
Restricted Stock [Member] \| Outgoing Non Employee Directors [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					1,356
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value					$ 14.73
Restricted Stock [Member] \| Employees [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					259,555
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value					$ 17.43
Minimum [Member] \| Restricted Stock [Member] \| Employee and Non-Employee Directors [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				1 year
Minimum [Member] \| Restricted Stock [Member] \| Employees [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					3 years
Maximum [Member] \| Restricted Stock [Member] \| Employee and Non-Employee Directors [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				10 years
Maximum [Member] \| Restricted Stock [Member] \| Employees [Member] \| Stock Compensation Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period					5 years
Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense	$ 535,719		336,310	$ 1,610,229	$ 765,347
Cost of Sales [Member]
Allocated Share-based Compensation Expense	$ 54,700		$ 34,155	$ 164,101	$ 78,311