Note 5 - Deposits - Summary of Deposits (Details) - USD ($)	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Noninterest-bearing	$ 1,371,633,000	$ 1,604,750,000
Noninterest-bearing demand, percentage	36.50%	43.20%
Noninterest-bearing demand, percent increase (decrease)	(14.50%)
Interest-bearing checking	$ 541,168,000	$ 575,028,000
Interest-bearing checking, percentage	14.40%	15.50%
Interest-bearing checking, percent increase (decrease)	(5.90%)
Money market	$ 927,143,000	$ 776,723,000
Money market, percentage	24.70%	20.90%
Money market, percent increase (decrease)	19.40%
Savings	$ 314,606,000	$ 381,602,000
Savings, percentage	8.40%	10.30%
Savings, percent increase (decrease)	(17.60%)
Local Time, under $100,000	$ 144,052,000	$ 113,099,000
Local Time, under $100,000, percentage	3.80%	3.00%
Local Time, under $100,000, percent increase (decrease)	27.40%
Local Time, $100,000 and over	$ 346,908,000	$ 261,609,000
Local Time, $100,000 and over, percentage	9.20%	7.10%
Local Time, $100,000 and over, percent increase (decrease)	32.60%
Total local deposits	$ 3,645,510,000	$ 3,712,811,000
Total local deposits, percentage	97.00%	100.00%
Total local deposits	(1.80%)
Out-of-area time, $100,000 and over	$ 111,279,000	$ 0
Out-of-area time, $100,000 and over, percentage	3.00%	0.00%
Total deposits	$ 3,756,789,000	$ 3,712,811,000
Total deposits, percentage	100.00%	100.00%
Total deposits, percent increase (decrease)	1.20%