Note 13 - Income Taxes - Reconciliation Between the Federal Statutory Income Tax Rate and the Company's Effective Tax Rate (Details)	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Federal statutory rate	35.00%	35.00%	35.00%
State tax, net of Federal benefit	5.92%	4.86%	5.31%
Other, mainly tax exempt leases	(0.32%)	(1.36%)	(1.41%)
Derecognition of uncertain tax positions
Effective rate	40.60%	38.50%	38.90%

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Section S99
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

+ References

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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