Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Allowance for doubtful accounts	$ 153,171	$ 122,095
Preferred stock, shares authorized (in shares)	1,250,000	1,250,000
Preferred stock - shares issued (in shares)	0	0
Preferred stock - shares outstanding (in shares)	0	0
Preferred stock - no par value (in dollars per share)	$ 0	$ 0
Common stock shares authorized (in shares)	250,000,000	250,000,000
Common stock shares issued (in shares)	10,448,283	10,685,599
Common stock shares outstanding (in shares)	10,448,283	10,685,599
Common stock - no par value (in dollars per share)	$ 0	$ 0

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section 50
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