Note 4 - Fair Value Measurements - Fair Value by Major Security Type (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Cost Basis		$ 301,193
Unrealized Gains (Losses)
Fair Value	95,538	301,193
Cash Equivalents	95,538	301,193
Short-term marketable securities
Long-term marketable securities
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Certificates of Deposit [Member]
Cost Basis	3,236,168	3,296,238
Unrealized Gains (Losses)
Fair Value	3,236,168	3,296,238
Short-term marketable securities	1,299,133	249,072
Long-term marketable securities	1,937,035	3,047,166
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Cost Basis	140,637	654,205
Unrealized Gains (Losses)		293
Fair Value	140,637	654,498
Cash Equivalents		160,058
Short-term marketable securities	140,637	494,440
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Corporate Debt Securities [Member]
Cost Basis	1,748,404	509,029
Unrealized Gains (Losses)	(1,549)	(594)
Fair Value	1,746,855	508,435
Short-term marketable securities	1,496,354	508,435
Long-term marketable securities	250,501
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Cost Basis	5,125,209	4,459,472
Unrealized Gains (Losses)	(1,549)	(301)
Fair Value	5,123,660	4,459,171
Cash Equivalents		160,058
Short-term marketable securities	2,936,124	1,251,947
Long-term marketable securities	2,187,536	3,047,166
Fair Value, Measurements, Nonrecurring [Member]
Cost Basis	5,125,209	4,760,665
Unrealized Gains (Losses)	(1,549)	(301)
Fair Value	5,219,198	4,760,364
Cash Equivalents	95,538	461,251
Short-term marketable securities	2,936,124	1,251,947
Long-term marketable securities	2,187,536	3,047,166
Short-term marketable securities	2,936,124	1,251,947
Long-term marketable securities	$ 2,187,536	$ 3,047,166

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Total debt and equity financial instruments including: (1) securities held-to-maturity and (2) securities available-for-sale that will be held for the long-term.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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