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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Ratio of Allowance for Loan Losses to End of Period Loans, Excluding PPP Loans		1.04%	1.13%	1.16%
Financing Receivable, Troubled Debt Restructuring	$ 6,120	$ 6,120	$ 4,340	$ 4,249
Financing Receivable, Modifications, Number of Contracts	2	3
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts		0	0
Amortizing Payments and Reduced Interest Rate [Member]
Financing Receivable, Modifications, Number of Contracts		1
Re-amortization and Reduced Interest Rate [Member]
Financing Receivable, Modifications, Number of Contracts		2

X

- Definition

Represents ratio of allowance for loan losses, excluding PPP loans, to the end of period loans, net of unearned income and deferred fees.

+ References

No definition available.

+ Details

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X

- 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

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ 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

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-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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X

- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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