Note 6 - Treasury Stock (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Treasury Stock, Shares, Ending Balance (in shares)	808,139	796,090
Treasury Stock, Value, Ending Balance	$ 1,618	$ 1,612

The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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