Note 12 - Shareholders' Equity - Dividends Declared (Details)	12 Months Ended
Dec. 31, 2019 USD ($)
Dividends Declared 2 [Member]
Declaration Date	Jan. 31, 2019
Total Amount	$ 1,064,484
Record Date	Feb. 15, 2019
Dividends Declared 3 [Member]
Declaration Date	May 17, 2019
Total Amount	$ 844,087
Record Date	May 31, 2019
Dividends Declared 4 [Member]
Declaration Date	Aug. 16, 2019
Total Amount	$ 772,977
Record Date	Aug. 30, 2019
Dividends Declared 5 [Member]
Declaration Date	Nov. 15, 2019
Total Amount	$ 773,982
Record Date	Nov. 29, 2019

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=118951113&loc=d3e6935-107765

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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