Note 4 - Loans - Impaired Loans and Related Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Loans with no related allowance, unpaid principal balance	$ 46,336	$ 58,816
Loans with no related allowance, recorded investment	38,401	53,578
Loans with related allowance, unpaid principal balance	38,272	49,842
Loans with related allowance, recorded investment	27,445	41,827
Allowance	4,547	6,429
Unpaid principal balance	84,608	108,658
Recorded investment	65,846	95,405
Commercial Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	15,879	23,784
Loans with no related allowance, recorded investment	11,342	20,698
Loans with related allowance, unpaid principal balance	14,294	13,703
Loans with related allowance, recorded investment	5,217	6,372
Allowance	894	1,030
Commercial Real Estate Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	24,437	22,877
Loans with no related allowance, recorded investment	21,209	22,287
Loans with related allowance, unpaid principal balance	17,930	31,134
Loans with related allowance, recorded investment	16,964	31,003
Allowance	3,631	5,254
Real Estate Construction Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance		5,776
Loans with no related allowance, recorded investment		4,286
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	6,020	6,379
Loans with no related allowance, recorded investment	5,850	6,307
Loans with related allowance, unpaid principal balance	6,048	5,005
Loans with related allowance, recorded investment	5,264	4,452
Allowance	$ 22	$ 145