Note 4 - Loans - Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
No. of Contracts	5	24	34
Pre-Modification Outstanding Recorded Investment	$ 5,417	$ 25,979	$ 29,130
Post-Modification Outstanding Recorded Investment	5,417	21,916	29,130
Specific Reserve	0	2,190	1,518
Charge-offs	$ 0	$ 4,063	$ 0
Commercial Portfolio Segment [Member]
No. of Contracts	5	23	23
Pre-Modification Outstanding Recorded Investment	$ 5,417	$ 25,937	$ 13,290
Post-Modification Outstanding Recorded Investment	5,417	21,874	13,290
Specific Reserve	0	2,190	1,384
Charge-offs	$ 0	$ 4,063	$ 0
Residential Mortgage and Equity Lines Portfolio Segment [Member]
No. of Contracts		1	4
Pre-Modification Outstanding Recorded Investment		$ 42	$ 1,214
Post-Modification Outstanding Recorded Investment		42	1,214
Specific Reserve		0	23
Charge-offs		$ 0	$ 0
Commercial Real Estate Portfolio Segment [Member]
No. of Contracts			7
Pre-Modification Outstanding Recorded Investment			$ 14,626
Post-Modification Outstanding Recorded Investment			14,626
Specific Reserve			111
Charge-offs			$ 0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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