Note 5 - Deposits - Summary of Deposits (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Noninterest-bearing	$ 1,134,995	$ 1,247,640
Noninterest-bearing demand, percentage	28.30%	32.10%
Noninterest-bearing demand, percent increase (decrease)	(9.00%)
Interest-bearing checking	$ 622,287	$ 635,790
Interest-bearing checking, percentage	15.50%	16.30%
Interest-bearing checking, percent increase (decrease)	(2.10%)
Money market	$ 1,137,877	$ 957,434
Money market, percentage	28.40%	24.50%
Money market, percent increase (decrease)	18.80%
Savings	$ 259,556	$ 262,566
Savings, percentage	6.50%	6.70%
Savings, percent increase (decrease)	(1.10%)
Local Time, under $100,000	$ 187,249	$ 175,741
Local Time, under $100,000, percentage	4.70%	4.50%
Local Time, under $100,000, percent increase (decrease)	6.50%
Local Time, $100,000 and over	$ 492,734	$ 453,366
Local Time, $100,000 and over, percentage	12.30%	11.60%
Local Time, $100,000 and over, percent increase (decrease)	8.70%
Total local deposits	$ 3,834,698	$ 3,732,537
Total local deposits, percentage	95.70%	95.70%
Total local deposits	2.70%
Out-of-area time, $100,000 and over	$ 173,112	$ 168,381
Out-of-area time, $100,000 and over, percentage	4.30%	4.30%
Out-of-area time, $100,000 and over, percent increase (decrease)	2.80%
Total deposits	$ 4,007,810	$ 3,900,918
Total deposits, percentage	100.00%	100.00%
Total deposits, percent increase (decrease)	2.70%