Note 6 - Treasury Stock (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Treasury Stock, Shares, Ending Balance (in shares)	963,509	948,347
Treasury Stock, Value, Ending Balance	$ 2,234	$ 2,182

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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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
-Topic 505
-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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