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Bank Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Bank premises and equipment
Less: accumulated depreciation	$ (498,641)	$ (468,167)
Bank premises and equipment, net	506,595	506,899
Bank Building and Improvements
Bank premises and equipment
Bank premises and equipment, gross	$ 573,257	563,302
Bank Building and Improvements | Minimum
Bank premises and equipment
Estimated useful lives	5 years
Bank Building and Improvements | Maximum
Bank premises and equipment
Estimated useful lives	40 years
Furniture, Equipment and Vehicles
Bank premises and equipment
Bank premises and equipment, gross	$ 313,880	292,958
Furniture, Equipment and Vehicles | Minimum
Bank premises and equipment
Estimated useful lives	1 year
Furniture, Equipment and Vehicles | Maximum
Bank premises and equipment
Estimated useful lives	20 years
Land
Bank premises and equipment
Bank premises and equipment, gross	$ 118,099	$ 118,806
Land, Building, Furniture, Fixture and Equipment | Minimum
Bank premises and equipment
Estimated useful lives	7 years
Land, Building, Furniture, Fixture and Equipment | Maximum
Bank premises and equipment
Estimated useful lives	27 years

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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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+ References

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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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