Note 8 - Cash Dividends (Details Textual) - USD ($)	12 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	Aug. 31, 2017
Payments of Ordinary Dividends, Common Stock	$ 5,048,000	$ 4,214,000	$ 2,900,000
Dividends Accrued	$ 30,067	$ 10,625
Subsequent Event [Member]
Quarterly Indicated Per Share Dividend Rate				$ 0.05

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Balance Type:	credit
Period Type:	duration