Premises and Equipment - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 102,718	$ 99,544
Accumulated depreciation	(60,988)	(56,842)
Total	41,730	42,702
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	6,266	6,266
Premises
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	52,423	51,799
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	36,911	34,836
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 7,118	$ 6,643

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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