Premises And Equipment - Major Categories of Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Premises and Equipment, Gross	$ 170,218	$ 156,386
Less accumulated depreciation	(110,447)	(100,485)
Premises and equipment, net	59,771	55,901
Land
Property, Plant and Equipment [Line Items]
Premises and Equipment, Gross	20,062	19,603
Buildings
Property, Plant and Equipment [Line Items]
Premises and Equipment, Gross	79,706	77,711
Equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Premises and Equipment, Gross	65,659	55,799
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and Equipment, Gross	$ 4,791	$ 3,273

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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