Note 6 - Premises and Equipment - Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, plant, and equipment, gross	$ 201,463	$ 196,593
Less: Accumulated depreciation/amortization	97,224	93,404
Premises and equipment, net	104,239	103,189
Land and Land Improvements [Member]
Property, plant, and equipment, gross	42,476	42,476
Building and Building Improvements [Member]
Property, plant, and equipment, gross	79,819	79,389
Furniture Fixtures and Equipment [Member]
Property, plant, and equipment, gross	60,141	56,503
Leasehold Improvements [Member]
Property, plant, and equipment, gross	17,380	17,075
Construction in Progress [Member]
Property, plant, and equipment, gross	$ 1,647	$ 1,150

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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