Premises and Equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Premises and Equipment
Premises and equipment, gross	$ 232,768	$ 192,650
Less accumulated depreciation	81,501	74,978
Total premises and equipment, net	151,267	117,672
Depreciation expense	11,879	9,556	$ 8,615
Land and improvements
Premises and Equipment
Premises and equipment, gross	43,967	36,453
Buildings and improvements
Premises and Equipment
Premises and equipment, gross	134,473	108,137
Furniture and equipment
Premises and Equipment
Premises and equipment, gross	$ 54,328	$ 48,060

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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