Note 11 - Stock-based Compensation - Compensation Expense Related to Stock Options (Details) - Share-based Payment Arrangement, Option [Member]	6 Months Ended
Mar. 31, 2019 USD ($)
Fiscal Year 2017 Grants [Member]
Compensation expense	$ 9,188
Fiscal Year 2019 [Member]
Compensation expense	$ 51,901

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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