Premises and Equipment - Summary of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Land	$ 94,929	$ 96,118
Buildings	513,290	482,182
Leasehold improvements	302,246	262,438
Premises and equipment, gross	1,726,796	1,594,694
Less: accumulated depreciation and amortization	977,912	890,697
Right of use assets — operating leases	412,674	436,927
Premises and equipment, net	1,161,558	1,140,924
Owned Assets [Member]
Property, Plant and Equipment [Line Items]
Furniture and equipment	807,701	739,724
Less: accumulated depreciation and amortization	971,979	882,272
Capital Leases [Member]
Property, Plant and Equipment [Line Items]
Furniture and equipment	8,630	14,232
Less: accumulated depreciation and amortization	$ 5,933	$ 8,425

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 of lessee's right to use underlying asset under operating lease.

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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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