Note 4 - Loans - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($)	Jun. 30, 2021	Jun. 30, 2020 USD ($)
Financing receivable modifications	$ 654		$ 654
Number of contracts	1	0	1
Pre-modification outstanding recorded investment	$ 654		$ 654
Post-modification outstanding recorded investment	654		654
Extended Maturity [Member]
Financing receivable modifications	0		0
Payment Deferral [Member]
Financing receivable modifications	$ 654		$ 654
Commercial Real Estate Portfolio Segment [Member]
Number of contracts	1		1
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Financing receivable modifications	$ 654		$ 654
Number of contracts	1		1
Pre-modification outstanding recorded investment	$ 654		$ 654
Post-modification outstanding recorded investment	654		654
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member] \| Extended Maturity [Member]
Financing receivable modifications	0		0
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member] \| Payment Deferral [Member]
Financing receivable modifications	$ 654		$ 654

Amount of financing receivable modified during period classified as troubled debt restructuring.

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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=123577603&loc=SL6953676-111524

+ Details

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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

+ Details

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