Note 15 - Fair Value Measurements - Assets Measured At Fair Value on a Non-recurring Basis and Quantitative Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Recorded investment	$ 15,786	$ 12,417
Related allowance	473	657
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member] \| Valuation, Market Approach [Member] \| Impaired Loans, Collateral Dependent [Member]
Recorded investment	7,721	8,020
Related allowance	376	606
Fair Value	$ 7,345	$ 7,414
Selling Cost	10.00%	10.00%
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member] \| Valuation, Market Approach [Member] \| Other Real Estate Owned [Member]
Recorded investment	$ 289	$ 919
Related allowance
Fair Value	$ 289	$ 919
Selling Cost	10.00%	10.00%
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member] \| Valuation, Income Approach [Member] \| Impaired Loans, Other [Member]
Recorded investment	$ 8,065	$ 4,397
Related allowance	97	51
Fair Value	$ 7,968	$ 4,346
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member] \| Valuation, Income Approach [Member] \| Impaired Loans, Other [Member] \| Minimum [Member]
Selling Cost	3.99%	3.70%
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member] \| Valuation, Income Approach [Member] \| Impaired Loans, Other [Member] \| Maximum [Member]
Selling Cost	7.49%	7.50%

The costs rate of selling collateral.

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- Definition

The fair value of impaired financing receivable recorded investment.

+ References

No definition available.

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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