Note 6 - Premises and Equipment - Summary of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Premises and equipment, gross	$ 75,049	$ 75,325
Accumulated depreciation and amortization	(33,394)	(32,941)
Total premises and equipment	41,655	42,384
Land [Member]
Premises and equipment, gross	7,118	7,118
Building and Building Improvements [Member]
Premises and equipment, gross	47,924	47,398
Furniture and Equipment [Member]
Premises and equipment, gross	18,511	20,758
Construction in Progress [Member]
Premises and equipment, gross	$ 1,496	$ 51

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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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