Note 8 - Loans - Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)
No. of Contracts	1	11
Pre-Modification Outstanding Recorded Investment	$ 1,948	$ 17,551
Post-Modification Outstanding Recorded Investment	1,622	17,551
Charge-offs
Specific reserve		$ 142
Commercial Portfolio Segment [Member]
No. of Contracts	1	3
Pre-Modification Outstanding Recorded Investment	$ 1,948	$ 2,463
Post-Modification Outstanding Recorded Investment	1,622	2,463
Charge-offs
Specific reserve
Commercial Real Estate Portfolio Segment [Member]
No. of Contracts		6
Pre-Modification Outstanding Recorded Investment		$ 14,287
Post-Modification Outstanding Recorded Investment		14,287
Charge-offs
Specific reserve		$ 134
Residential Mortgage and Equity Lines Portfolio Segment [Member]
No. of Contracts		2
Pre-Modification Outstanding Recorded Investment		$ 801
Post-Modification Outstanding Recorded Investment		801
Charge-offs
Specific reserve		$ 8

The amount of specific reserve for allowance for credit losses.

No definition available.

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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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- Definition

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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