Premises and Equipment (Components Of Premises And Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Land	$ 33,835	$ 34,161
Buildings and improvements	206,889	204,639
Furniture, fixtures and equipment	138,295	136,403
Software	108,244	104,802
Construction in progress and other	12,137	16,432
Total premises and equipment	499,400	496,437
Less: Accumulated depreciation and amortization	(321,350)	(294,977)
Premises and equipment, net	$ 178,050	$ 201,460
Building and Building Improvements \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years
Building and Building Improvements \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	39 years
Office Equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	4 years
Office Equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Software \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Software \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years

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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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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