Note 4 - Loans - Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
No. of Contracts	24	34	31
Pre-Modification Outstanding Recorded Investment	$ 25,979	$ 29,130	$ 77,741
Post-Modification Outstanding Recorded Investment	21,916	29,130	77,436
Specific Reserve	2,190	1,518	1,556
Charge-offs	$ 4,063	$ 0	$ 305
Commercial Portfolio Segment [Member]
No. of Contracts	23	23	16
Pre-Modification Outstanding Recorded Investment	$ 25,937	$ 13,290	$ 29,590
Post-Modification Outstanding Recorded Investment	21,874	13,290	29,590
Specific Reserve	2,190	1,384	7
Charge-offs	$ 4,063	$ 0	$ 0
Residential Mortgage and Equity Lines Portfolio Segment [Member]
No. of Contracts	1	4	4
Pre-Modification Outstanding Recorded Investment	$ 42	$ 1,214	$ 1,088
Post-Modification Outstanding Recorded Investment	42	1,214	1,088
Specific Reserve	0	23	53
Charge-offs	$ 0	$ 0	$ 0
Commercial Real Estate Portfolio Segment [Member]
No. of Contracts		7	9
Pre-Modification Outstanding Recorded Investment		$ 14,626	$ 19,380
Post-Modification Outstanding Recorded Investment		14,626	19,075
Specific Reserve		111	1,496
Charge-offs		$ 0	$ 305
Real Estate Construction Portfolio Segment [Member]
No. of Contracts			2
Pre-Modification Outstanding Recorded Investment			$ 27,683
Post-Modification Outstanding Recorded Investment			27,683
Specific Reserve			0
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=118936363&loc=SL6953676-111524

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

+ References

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- Definition

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=118939409&loc=d3e18845-111554

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