Bank Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Bank premises and equipment
Less: accumulated depreciation	$ (556,665)	$ (542,159)
Bank premises and equipment, net	431,612	447,082
Bank buildings and improvements [Member]
Bank premises and equipment
Bank premises and equipment, gross	$ 571,665	573,276
Bank buildings and improvements [Member] \| Minimum
Bank premises and equipment
Estimated useful lives	5 years
Bank buildings and improvements [Member] \| Maximum [Member]
Bank premises and equipment
Estimated useful lives	39 years
Furniture equipment and Vehicles [Member]
Bank premises and equipment
Bank premises and equipment, gross	$ 307,990	302,847
Furniture equipment and Vehicles [Member] \| Minimum
Bank premises and equipment
Estimated useful lives	1 year
Furniture equipment and Vehicles [Member] \| Maximum [Member]
Bank premises and equipment
Estimated useful lives	20 years
Land [Member]
Bank premises and equipment
Bank premises and equipment, gross	$ 108,622	$ 113,118

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ 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.

+ References

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