Note 3 - Loans and Allowance for Loan Losses - Components of Loan Portfolio (Details) - USD ($)		9 Months Ended
		Sep. 30, 2021	Dec. 31, 2020
Loans		$ 3,313,709,000	$ 3,193,470,000
Percent of portfolio		100.00%	100.00%
Period increase (decrease)		3.80%
Commercial Portfolio Segment [Member]
Loans		$ 2,842,359,000	$ 2,793,962,000
Percent of portfolio		85.80%	87.50%
Period increase (decrease)		1.70%
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Loans	[1]	$ 1,074,394,000	$ 1,145,423,000
Percent of portfolio	[1]	32.40%	35.90%
Period increase (decrease)	[1]	(6.20%)
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Loans		$ 38,380,000	$ 55,055,000
Percent of portfolio		1.20%	1.70%
Period increase (decrease)		(30.30%)
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
Loans		$ 551,762,000	$ 529,953,000
Percent of portfolio		16.70%	16.60%
Period increase (decrease)		4.10%
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
Loans		$ 998,697,000	$ 917,436,000
Percent of portfolio		30.10%	28.70%
Period increase (decrease)		8.90%
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Loans		$ 179,126,000	$ 146,095,000
Percent of portfolio		5.40%	4.60%
Period increase (decrease)		22.60%
Retail Portfolio Segment [Member]
Loans		$ 471,350,000	$ 399,508,000
Percent of portfolio		14.20%	12.50%
Period increase (decrease)		18.00%
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
Loans		$ 59,732,000	$ 61,620,000
Percent of portfolio		1.80%	1.90%
Period increase (decrease)		(3.10%)
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
Loans		$ 411,618,000	$ 337,888,000
Percent of portfolio		12.40%	10.60%
Period increase (decrease)		21.80%

[1] Includes $116 million and $365 million in loans originated under the Paycheck Protection Program for September 30, 2021 and December 31, 2020, respectively.