Premises and Equipment - Summary of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Land	$ 97,082	$ 98,077
Buildings	465,482	454,610
Leasehold improvements	240,731	239,956
Premises and equipment, gross	1,491,659	1,487,347
Less: accumulated depreciation and amortization	844,251	840,896
Premises and equipment, net	647,408	646,451
Owned Assets [Member]
Property, Plant and Equipment [Line Items]
Furniture and equipment	669,782	676,665
Less: accumulated depreciation and amortization	835,218	830,832
Capital Leases [Member]
Property, Plant and Equipment [Line Items]
Furniture and equipment	18,582	18,039
Less: accumulated depreciation and amortization	$ 9,033	$ 10,064

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 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 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 of additions or improvements to assets held under a lease arrangement.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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