Note 6 - Investments in Affordable Housing and Alternative Energy Partnerships - Investments in Affordable Housing and Alternative Energy Partnerships (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 30, 2022	Dec. 31, 2021
Investments in affordable housing partnerships, net	$ 289,920		$ 287,517
Other borrowings for affordable housing limited partnerships	22,600		23,145
Investments in affordable housing and alternative energy partnerships, unfunded commitments	133,491		107,652
Investments in alternative energy tax credit partnerships, net	$ 37,208	$ 37,200	$ 11,694