Note 21 - Fair Value Measurements and Fair Values of Financial Instruments - Assets Measured at Fair Value (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Total, fair value	$ 346,723,000	$ 363,273,000
Marketable equity security	979,000	950,000
Unpaid principal - with allowance	3,375,000	4,851,000
Valuation allowance	(1,051,000)	(1,605,000)
Impaired loans, net	3,375,000	4,851,000
US Government Agencies Debt Securities [Member]
Total, fair value	17,000,000	12,500,000
Obligations of States and Political Subdivisions Tax Exempt [Member]
Total, fair value	70,760,000	83,952,000
Obligations of States and Political Subdivisions Taxable [Member]
Total, fair value	36,303,000	27,699,000
Residential Pass-Through Securities [Member]
Total, fair value	59,210,000	53,445,000
Residential Collateralized Mortgage Obligations [Member]
Total, fair value	114,723,000	145,912,000
Commercial Mortgage Backed Securities [Member]
Total, fair value	48,727,000	39,765,000
Fair Value, Recurring [Member]
Total, fair value	346,723,000	363,273,000
Marketable equity security	979,000	950,000
Servicing rights	1,277,000	1,404,000
Total asset fair value measurements	348,979,000	365,627,000
Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Total, fair value	17,000,000	15,500,000
Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Tax Exempt [Member]
Total, fair value	70,760,000	83,952,000
Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Taxable [Member]
Total, fair value	36,303,000	27,699,000
Fair Value, Recurring [Member] \| Residential Pass-Through Securities [Member]
Total, fair value	59,210,000	53,445,000
Fair Value, Recurring [Member] \| Residential Collateralized Mortgage Obligations [Member]
Total, fair value	114,723,000	145,912,000
Fair Value, Recurring [Member] \| Commercial Mortgage Backed Securities [Member]
Total, fair value	48,727,000	39,765,000
Fair Value, Nonrecurring [Member]
Total asset fair value measurements	5,210,000	4,949,000
Unpaid principal - with allowance	3,375,000	4,851,000
Valuation allowance	(1,051,000)	(1,605,000)
Impaired loans, net	2,324,000	3,246,000
Foreclosed assets held for sale	2,886,000	1,703,000
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Total, fair value	0	0
Marketable equity security	979,000	950,000
Servicing rights	0	0
Total asset fair value measurements	979,000	950,000
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Tax Exempt [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Taxable [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Residential Pass-Through Securities [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Residential Collateralized Mortgage Obligations [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member] \| Commercial Mortgage Backed Securities [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Nonrecurring [Member]
Total asset fair value measurements	0	0
Unpaid principal - with allowance	0	0
Valuation allowance	0	0
Impaired loans, net	0	0
Foreclosed assets held for sale	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Total, fair value	346,723,000	363,273,000
Marketable equity security	0	0
Servicing rights	0	0
Total asset fair value measurements	346,723,000	363,273,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Total, fair value	17,000,000	12,500,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Tax Exempt [Member]
Total, fair value	70,760,000	83,952,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Taxable [Member]
Total, fair value	36,303,000	27,699,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Residential Pass-Through Securities [Member]
Total, fair value	59,210,000	53,445,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Residential Collateralized Mortgage Obligations [Member]
Total, fair value	114,723,000	145,912,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member] \| Commercial Mortgage Backed Securities [Member]
Total, fair value	48,727,000	39,765,000
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Nonrecurring [Member]
Total asset fair value measurements	0	0
Unpaid principal - with allowance	0	0
Valuation allowance	0	0
Impaired loans, net	0	0
Foreclosed assets held for sale	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Total, fair value	0	0
Marketable equity security	0	0
Servicing rights	1,277,000	1,404,000
Total asset fair value measurements	1,277,000	1,404,000
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| US Government Agencies Debt Securities [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Tax Exempt [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Obligations of States and Political Subdivisions Taxable [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Residential Pass-Through Securities [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Residential Collateralized Mortgage Obligations [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Commercial Mortgage Backed Securities [Member]
Total, fair value	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Nonrecurring [Member]
Total asset fair value measurements	5,210,000	4,949,000
Unpaid principal - with allowance	3,375,000	4,851,000
Valuation allowance	(1,051,000)	(1,605,000)
Impaired loans, net	2,324,000	3,246,000
Foreclosed assets held for sale	$ 2,886,000	$ 1,703,000

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit losses related to recorded investment.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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