Note 6 - Other Assets - Summary of Major Components of Other Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Cash surrender value of life insurance other than BOLI	$ 18,773	$ 17,843
Net deferred tax asset	49,181	47,236
Investments in tax credit partnerships	173,055	175,056
Swap assets	10,823	5,133
Prepaid assets	6,255	5,873
WM&T fees receivable	4,551	4,205
Mortgage servicing rights	12,544	13,082	$ 14,623	$ 15,219
Other real estate owned	10	10
Other	72,420	18,922
Total other assets	$ 347,612	$ 287,360