Premises and Equipment - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 122,788	$ 102,718
Accumulated depreciation	(65,848)	(60,988)
Total	56,940	41,730
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	9,018	6,266
Premises
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	60,767	52,423
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	41,713	36,911
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 11,290	$ 7,118

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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