Note 4 - Premises and Equipment, Net - Summary of Premises and Equipment (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Property, plant and equipment, gross	$ 89,483,000	$ 94,253,000
Less: accumulated depreciation	37,366,000	36,955,000
Premises and equipment, net	52,117,000	57,298,000
Land and Land Improvements [Member]
Property, plant and equipment, gross	13,517,000	15,111,000
Building [Member]
Property, plant and equipment, gross	52,960,000	56,168,000
Furniture and Fixtures [Member]
Property, plant and equipment, gross	$ 23,006,000	$ 22,974,000