Note 18 - Fair Values of Financial Instruments - Credit Loss Roll Forward for Trust Preferred Securities Classified with Other Than Temporary Impairment (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Ending balance, December 31, 2018	$ 235
Reduction due to sale of security	(62)
Ending balance, December 31, 2019	$ 173

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=SL6284393-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=SL6284393-111563

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant