Note 3 - Loans and Allowance for Credit Losses - Components of Loan Portfolio (Details) - USD ($)		3 Months Ended
		Mar. 31, 2023	Dec. 31, 2022
Loans		$ 3,965,528,000	$ 3,916,619,000
Percent of portfolio		100.00%	100.00%
Period increase (decrease)		1.20%
Commercial Portfolio Segment [Member]
Loans		$ 3,140,420,000	$ 3,131,830,000
Percent of portfolio		79.20%	80.00%
Period increase (decrease)		0.30%
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans	[1]	$ 1,173,440,000	$ 1,185,083,000
Percent of portfolio	[1]	29.60%	30.30%
Period increase (decrease)	[1]	(1.00%)
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans		$ 66,233,000	$ 61,873,000
Percent of portfolio		1.70%	1.60%
Period increase (decrease)		7.00%
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans		$ 630,187,000	$ 639,192,000
Percent of portfolio		15.90%	16.30%
Period increase (decrease)		(1.40%)
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans		$ 1,051,221,000	$ 1,033,734,000
Percent of portfolio		26.50%	26.40%
Period increase (decrease)		1.70%
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans		$ 219,339,000	$ 211,948,000
Percent of portfolio		5.50%	5.40%
Period increase (decrease)		3.50%
Retail Portfolio Segment [Member]
Loans		$ 825,108,000	$ 784,789,000
Percent of portfolio		20.80%	20.00%
Period increase (decrease)		5.10%
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans		$ 795,007,000	$ 755,036,000
Percent of portfolio		20.00%	19.30%
Period increase (decrease)		5.30%
Retail Portfolio Segment [Member] | Other Consumer Loans [Member]
Loans		$ 30,101,000	$ 29,753,000
Percent of portfolio		0.80%	0.70%
Period increase (decrease)		1.20%

[1] For March 31, 2023, and December 31, 2022, includes $0.4 million and $0.9 million in loans originated under the Paycheck Protection Program, respectively.