Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 557,103	$ 536,550
Less: Accumulated depreciation and amortization	(317,057)	(302,021)
Premises and equipment, net	240,046	234,529
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	38,836	35,160
Buildings and improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	350,609	325,831
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	158,064	150,566
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 9,594	$ 24,993

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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