Note 6 - Premises and Equipment - Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, plant, and equipment, gross	$ 205,144	$ 201,463
Less: Accumulated depreciation/amortization	102,146	97,224
Premises and equipment, net	102,998	104,239
Land and Land Improvements [Member]
Property, plant, and equipment, gross	42,476	42,476
Building and Building Improvements [Member]
Property, plant, and equipment, gross	79,953	79,819
Furniture Fixtures and Equipment [Member]
Property, plant, and equipment, gross	62,835	60,141
Leasehold Improvements [Member]
Property, plant, and equipment, gross	17,819	17,380
Construction in Progress [Member]
Property, plant, and equipment, gross	$ 2,061	$ 1,647

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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