Note 10 - Acquisitions - Pro Forma Information (Details) - Calix, Inc. [Member] - USD ($)	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Net sales	$ 17,823,216	$ 20,974,827	$ 37,005,214	$ 44,720,355
Income (loss) from operations	(341,314)	1,937,346	602,596	4,184,133
Net income (loss)	$ (166,775)	$ 1,352,108	$ 1,157,992	$ 2,973,195
Basic (in dollars per share)	$ (0.01)	$ 0.10	$ 0.09	$ 0.22
Diluted (in dollars per share)	$ (0.01)	$ 0.10	$ 0.09	$ 0.22

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-Paragraph 2
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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