Note 14 - Capital Structure and Stock-based Compensation (Details Textual) - USD ($)	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	Nov. 30, 1995
Common Stock, Shares Authorized	20,000,000	20,000,000
Preferred Stock, Shares Authorized	2,500,000	2,500,000
Share-based Compensation	$ 4,800	$ 4,500	$ 4,400
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	11,400
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 5,700
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(4,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 12,418	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0	0	0
The 1995 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				1,000,000
Increase in Maximun Number of Available Shares of Common Stock, Percentage				1.00%

The percentage increase in the maximum number of available shares of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 45
-Paragraph 28
-Subparagraph (a)
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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

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