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Premises and Equipment (Schedule of Premises and Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Gross land, buildings and equipment	$ 944,353	$ 923,097
Less accumulated depreciation and amortization	573,270	552,460
Net premises and equipment	371,083	370,637
Land [Member]
Property, Plant and Equipment [Line Items]
Gross land, buildings and equipment	93,492	91,678
Building and improvements [Member]
Property, Plant and Equipment [Line Items]
Gross land, buildings and equipment	582,056	566,177
Equipment [Member]
Property, Plant and Equipment [Line Items]
Gross land, buildings and equipment	239,216	237,047
Right of use leased assets [Member]
Property, Plant and Equipment [Line Items]
Gross land, buildings and equipment	$ 29,589	$ 28,195

X

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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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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