Note 6 - Other Assets - Summary of Major Components of Other Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Cash surrender value of life insurance other than BOLI	$ 19,009		$ 17,843
Net deferred tax asset	50,246		47,236
Investments in tax credit partnerships	179,232		175,056
Swap assets	11,968		5,133
Prepaid assets	5,036		5,873
WM&T fees receivable	4,810		4,205
Mortgage servicing rights	12,197	$ 12,544	13,082	$ 14,116	$ 14,623	$ 15,219
Other real estate owned	10		10
Other	17,020		18,922
Total other assets	$ 299,528		$ 287,360