Note 3 - Securities - Gains on Sales of Available for Sale Securities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Proceeds	$ 248	$ 31,785	$ 248	$ 40,011
Gains	4	558	29	640
Losses	0	(1)	0	(5)
Tax provision related to gains (losses)	$ 1	$ 117	$ 6	$ 133

Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26853-111562

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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