Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Restructurings By Class (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
Number of contracts	1	2	1	6
Pre-modification outstanding principal balance	$ 98	$ 338	$ 98	$ 3,935
Post-modification outstanding principal balance	$ 98	$ 338	$ 98	$ 3,935
Residential Portfolio Segment [Member] \| Equity Lines [Member]
Number of contracts	1		1
Pre-modification outstanding principal balance	$ 98		$ 98
Post-modification outstanding principal balance	$ 98		$ 98
Residential Portfolio Segment [Member] \| Investor Owned Residential Real Estate [Member]
Number of contracts		2		2
Pre-modification outstanding principal balance		$ 338		$ 338
Post-modification outstanding principal balance		$ 338		$ 338
Real Estate Construction Portfolio Segment[Member] \| Construction, Other [Member]
Number of contracts				2
Pre-modification outstanding principal balance				$ 2,882
Post-modification outstanding principal balance				$ 2,882
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate, Owner Occupied [Member]
Number of contracts				2
Pre-modification outstanding principal balance				$ 715
Post-modification outstanding principal balance				$ 715

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

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.

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

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