Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
With no related allowance recorded, unpaid principal balance	$ 16,997,000	$ 26,892,000
With no related allowance recorded, principal balance	15,715,000	24,738,000
With no related allowance recorded, average recorded principal balance	19,857,000	17,315,000
With related allowance recorded, unpaid principal balance	3,671,000	2,266,000
With related allowance recorded, principal balance	3,651,000	2,220,000
Related allowance	546,000	551,000
With related allowance recorded, average recorded principal balance	3,440,000	2,742,000
Total unpaid principal balance	20,668,000	29,158,000
Total principal balance	19,366,000	26,958,000
Total average recorded principal balance	23,297,000	20,057,000
Commercial Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance	12,658,000	21,365,000
With no related allowance recorded, principal balance	12,583,000	21,176,000
With no related allowance recorded, average recorded principal balance	16,434,000	13,652,000
With related allowance recorded, unpaid principal balance	3,099,000	1,268,000
With related allowance recorded, principal balance	3,099,000	1,239,000
Related allowance	354,000	138,000
With related allowance recorded, average recorded principal balance	2,689,000	1,726,000
Total unpaid principal balance	15,757,000	22,633,000
Total principal balance	15,682,000	22,415,000
Total average recorded principal balance	19,123,000	15,378,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
With no related allowance recorded, unpaid principal balance	2,893,000	6,242,000
With no related allowance recorded, principal balance	2,818,000	6,242,000
With no related allowance recorded, average recorded principal balance	3,632,000	7,874,000
With related allowance recorded, unpaid principal balance	2,192,000	343,000
With related allowance recorded, principal balance	2,192,000	343,000
Related allowance	266,000	53,000
With related allowance recorded, average recorded principal balance	1,732,000	971,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
With no related allowance recorded, unpaid principal balance	0	0
With no related allowance recorded, principal balance	0	0
With no related allowance recorded, average recorded principal balance	0	187,000
With related allowance recorded, unpaid principal balance	0	0
With related allowance recorded, principal balance	0	0
Related allowance	0	0
With related allowance recorded, average recorded principal balance	0	77,000
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance	9,674,000	14,782,000
With no related allowance recorded, principal balance	9,674,000	14,593,000
With no related allowance recorded, average recorded principal balance	12,634,000	5,361,000
With related allowance recorded, unpaid principal balance	761,000	763,000
With related allowance recorded, principal balance	761,000	734,000
Related allowance	84,000	77,000
With related allowance recorded, average recorded principal balance	803,000	578,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance	0	341,000
With no related allowance recorded, principal balance	0	341,000
With no related allowance recorded, average recorded principal balance	131,000	227,000
With related allowance recorded, unpaid principal balance	146,000	162,000
With related allowance recorded, principal balance	146,000	162,000
Related allowance	4,000	8,000
With related allowance recorded, average recorded principal balance	154,000	100,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
With no related allowance recorded, unpaid principal balance	91,000	0
With no related allowance recorded, principal balance	91,000	0
With no related allowance recorded, average recorded principal balance	37,000	3,000
With related allowance recorded, unpaid principal balance	0	0
With related allowance recorded, principal balance	0	0
Related allowance	0	0
With related allowance recorded, average recorded principal balance	0	0
Retail Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance	4,339,000	5,527,000
With no related allowance recorded, principal balance	3,132,000	3,562,000
With no related allowance recorded, average recorded principal balance	3,423,000	3,663,000
With related allowance recorded, unpaid principal balance	572,000	998,000
With related allowance recorded, principal balance	552,000	981,000
Related allowance	192,000	413,000
With related allowance recorded, average recorded principal balance	751,000	1,016,000
Total unpaid principal balance	4,911,000	6,525,000
Total principal balance	3,684,000	4,543,000
Total average recorded principal balance	4,174,000	4,679,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
With no related allowance recorded, unpaid principal balance	1,173,000	1,072,000
With no related allowance recorded, principal balance	1,107,000	987,000
With no related allowance recorded, average recorded principal balance	1,096,000	1,216,000
With related allowance recorded, unpaid principal balance	160,000	300,000
With related allowance recorded, principal balance	140,000	283,000
Related allowance	123,000	241,000
With related allowance recorded, average recorded principal balance	214,000	421,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
With no related allowance recorded, unpaid principal balance	3,166,000	4,455,000
With no related allowance recorded, principal balance	2,025,000	2,575,000
With no related allowance recorded, average recorded principal balance	2,327,000	2,447,000
With related allowance recorded, unpaid principal balance	412,000	698,000
With related allowance recorded, principal balance	412,000	698,000
Related allowance	69,000	172,000
With related allowance recorded, average recorded principal balance	$ 537,000	$ 595,000