Note 3 - Loans and Allowance for Credit Losses - Components of Loan Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Loans	$ 4,322,006	$ 4,303,758
Percent of portfolio	100.00%	100.00%
Period increase (decrease)	0.40%
Commercial Portfolio Segment [Member]
Loans	$ 3,429,642	$ 3,415,299
Percent of portfolio	79.30%	79.40%
Period increase (decrease)	0.40%
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans	$ 1,222,637	$ 1,254,586
Percent of portfolio	28.30%	29.20%
Period increase (decrease)	(2.50%)
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans	$ 75,091	$ 74,753
Percent of portfolio	1.70%	1.70%
Period increase (decrease)	0.50%
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans	$ 719,338	$ 717,667
Percent of portfolio	16.60%	16.70%
Period increase (decrease)	0.20%
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans	$ 1,045,615	$ 1,035,684
Percent of portfolio	24.20%	24.10%
Period increase (decrease)	1.00%
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans	$ 366,961	$ 332,609
Percent of portfolio	8.50%	7.70%
Period increase (decrease)	10.30%
Retail Portfolio Segment [Member]
Loans	$ 892,364	$ 888,459
Percent of portfolio	20.70%	20.60%
Period increase (decrease)	0.40%
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans	$ 840,653	$ 837,406
Percent of portfolio	19.50%	19.50%
Period increase (decrease)	0.40%
Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Loans	$ 51,711	$ 51,053
Percent of portfolio	1.20%	1.10%
Period increase (decrease)	1.30%