Note 3 - Loans and Allowance for Loan Losses - Activity for Troubled Debt Restructurings (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Beginning Balance	$ 3,760,000	$ 12,204,000	$ 6,414,000	$ 8,587,000
Charge-Offs	0	0	0	0
Payments	(845,000)	(2,143,000)	(3,521,000)	(4,975,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	2,648,000	6,000	2,670,000	6,455,000
Ending Balance	5,563,000	10,067,000	5,563,000	10,067,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Beginning Balance	0	82,000	0	85,000
Charge-Offs	0	0	0	0
Payments	0	(2,000)	0	(5,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	0	0	0	0
Ending Balance	0	80,000	0	80,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Beginning Balance	13,887,000	3,811,000	14,797,000	1,145,000
Charge-Offs	0	0	0	0
Payments	(685,000)	(20,000)	(1,595,000)	(1,008,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	686,000	0	686,000	3,654,000
Ending Balance	13,888,000	3,791,000	13,888,000	3,791,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Beginning Balance	471,000	174,000	480,000	178,000
Charge-Offs	0	0	0	0
Payments	(318,000)	(4,000)	(327,000)	(8,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	0	0	0	0
Ending Balance	153,000	170,000	153,000	170,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Beginning Balance	0	3,000	0	7,000
Charge-Offs	0	0	0	0
Payments	0	(2,000)	0	(6,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	0	0	0	0
Ending Balance	0	1,000	0	1,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Beginning Balance	1,099,000	1,452,000	1,146,000	1,415,000
Charge-Offs	0	0	0	0
Payments	(115,000)	(175,000)	(232,000)	(203,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	412,000	438,000	482,000	503,000
Ending Balance	1,396,000	1,715,000	1,396,000	1,715,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Beginning Balance	820,000	715,000	806,000	724,000
Charge-Offs	0	0	0	0
Payments	(131,000)	(20,000)	(153,000)	(29,000)
Transfers to ORE	0	0	0	0
Net Additions/Deletions	10,000	20,000	46,000	20,000
Ending Balance	$ 699,000	$ 715,000	$ 699,000	$ 715,000