Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 536,550	$ 513,684
Less: Accumulated depreciation and amortization	(302,021)	(290,882)
Premises and equipment, net	234,529	222,802
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	35,160	35,560
Buildings and improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	325,831	307,332
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	150,566	150,876
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 24,993	$ 19,916

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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