Note 11 - Common Stock Repurchases (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Treasury Stock, Shares, Acquired	185,112	7,989
Treasury Stock, Value, Acquired, Cost Method	$ 158,000	$ 6,000

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
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-Subparagraph (SX 210.3-04)
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