Note 5 - Loans - Nonaccrual Loans and Related Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Loans with no related allowance, unpaid principal balance	$ 88,728	$ 74,673
Loans with no related allowance, recorded investment	66,681	54,140
Loans with related allowance, unpaid principal balance	0	16,539
Loans with related allowance, recorded investment	0	14,714
Allowance	0	3,941
Unpaid principal balance	88,728	91,212
Non-accrual loans	66,681	68,854
Commercial Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	26,310	27,341
Loans with no related allowance, recorded investment	14,404	12,949
Loans with related allowance, unpaid principal balance	0	14,643
Loans with related allowance, recorded investment	0	12,823
Allowance	0	3,734
Real Estate Construction Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	7,736
Loans with no related allowance, recorded investment	7,736
Commercial Real Estate Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	41,725	37,697
Loans with no related allowance, recorded investment	32,030	32,205
Loans with related allowance, unpaid principal balance	0	1,896
Loans with related allowance, recorded investment	0	1,891
Allowance	0	207
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Loans with no related allowance, unpaid principal balance	12,957	9,626
Loans with no related allowance, recorded investment	12,511	8,978
Loans with related allowance, unpaid principal balance	0
Loans with related allowance, recorded investment	0
Allowance	0
Installment and Other Loans [Member ]
Loans with no related allowance, unpaid principal balance	0	9
Loans with no related allowance, recorded investment	$ 0	$ 8