Premises and Equipment - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Premises and equipments
Premises and equipment, gross	$ 351,477	$ 331,250
Less accumulated depreciation	(135,501)	(125,110)
Premises and equipment, net	215,976	206,140
Land and land improvements
Premises and equipments
Premises and equipment, gross	81,150	78,066
Buildings and improvements
Premises and equipments
Premises and equipment, gross	170,629	153,980
Furniture and equipment
Premises and equipments
Premises and equipment, gross	97,997	93,854
Construction in progress
Premises and equipments
Premises and equipment, gross	$ 1,701	$ 5,350

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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