Note 7 - Premises and Equipment - Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, plant, and equipment, gross	$ 196,593	$ 191,015
Less: Accumulated depreciation/amortization	93,404	87,951
Premises and equipment, net	103,189	103,064
Land and Land Improvements [Member]
Property, plant, and equipment, gross	42,476	42,476
Building and Building Improvements [Member]
Property, plant, and equipment, gross	79,389	79,179
Furniture Fixtures and Equipment [Member]
Property, plant, and equipment, gross	56,503	53,529
Leasehold Improvements [Member]
Property, plant, and equipment, gross	17,075	15,496
Construction in Progress [Member]
Property, plant, and equipment, gross	$ 1,150	$ 335

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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