Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2021
With no related allowance recorded, unpaid principal balance			$ 16,997,000
With no related allowance recorded, principal balance			15,715,000
With no related allowance recorded, average recorded principal balance	$ 18,958,000	$ 20,892,000
With related allowance recorded, unpaid principal balance			3,671,000
With related allowance recorded, principal balance			3,651,000
Related allowance			546,000
With related allowance recorded, average recorded principal balance	4,703,000	3,387,000
Total unpaid principal balance			20,668,000
Total principal balance			19,366,000
Total average recorded principal balance	23,661,000	24,279,000
Commercial Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance			12,658,000
With no related allowance recorded, principal balance			12,583,000
With no related allowance recorded, average recorded principal balance	15,479,000	17,396,000
With related allowance recorded, unpaid principal balance			3,099,000
With related allowance recorded, principal balance			3,099,000
Related allowance			354,000
With related allowance recorded, average recorded principal balance	4,034,000	2,586,000
Total unpaid principal balance			15,757,000
Total principal balance			15,682,000
Total average recorded principal balance	19,513,000	19,982,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
With no related allowance recorded, unpaid principal balance			2,893,000
With no related allowance recorded, principal balance			2,818,000
With no related allowance recorded, average recorded principal balance	2,759,000	3,836,000
With related allowance recorded, unpaid principal balance			2,192,000
With related allowance recorded, principal balance			2,192,000
Related allowance			266,000
With related allowance recorded, average recorded principal balance	2,888,000	1,617,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
With no related allowance recorded, unpaid principal balance			0
With no related allowance recorded, principal balance			0
With no related allowance recorded, average recorded principal balance	0	0
With related allowance recorded, unpaid principal balance			0
With related allowance recorded, principal balance			0
Related allowance			0
With related allowance recorded, average recorded principal balance	0	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance			9,674,000
With no related allowance recorded, principal balance			9,674,000
With no related allowance recorded, average recorded principal balance	12,674,000	13,374,000
With related allowance recorded, unpaid principal balance			761,000
With related allowance recorded, principal balance			761,000
Related allowance			84,000
With related allowance recorded, average recorded principal balance	994,000	813,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance			0
With no related allowance recorded, principal balance			0
With no related allowance recorded, average recorded principal balance	0	163,000
With related allowance recorded, unpaid principal balance			146,000
With related allowance recorded, principal balance			146,000
Related allowance			4,000
With related allowance recorded, average recorded principal balance	152,000	156,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
With no related allowance recorded, unpaid principal balance			91,000
With no related allowance recorded, principal balance			91,000
With no related allowance recorded, average recorded principal balance	46,000	23,000
With related allowance recorded, unpaid principal balance			0
With related allowance recorded, principal balance			0
Related allowance			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
With no related allowance recorded, principal balance			3,132,000
With no related allowance recorded, average recorded principal balance	3,479,000	3,496,000
With related allowance recorded, unpaid principal balance			572,000
With related allowance recorded, principal balance			552,000
Related allowance			192,000
With related allowance recorded, average recorded principal balance	669,000	801,000
Total unpaid principal balance			4,911,000
Total principal balance			3,684,000
Total average recorded principal balance	4,148,000	4,297,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
With no related allowance recorded, unpaid principal balance			1,173,000
With no related allowance recorded, principal balance			1,107,000
With no related allowance recorded, average recorded principal balance	1,223,000	1,093,000
With related allowance recorded, unpaid principal balance			160,000
With related allowance recorded, principal balance			140,000
Related allowance			123,000
With related allowance recorded, average recorded principal balance	197,000	232,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
With no related allowance recorded, unpaid principal balance			3,166,000
With no related allowance recorded, principal balance			2,025,000
With no related allowance recorded, average recorded principal balance	2,256,000	2,403,000
With related allowance recorded, unpaid principal balance			412,000
With related allowance recorded, principal balance			412,000
Related allowance			$ 69,000
With related allowance recorded, average recorded principal balance	$ 472,000	$ 569,000