Note 9 - Cash Dividends (Details Textual) - USD ($)	6 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Jan. 31, 2018
Payments of Ordinary Dividends, Common Stock	$ 2,564,000	$ 2,513,000
Dividends Accrued	$ 38,463	$ 19,826
Subsequent Event [Member]
Quarterly Indicated Per Share Dividend Rate			$ 0.05
Annual Indicated per Share Dividend Rate			$ 0.20

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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration