Premises and Equipment - Summary of Premises and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Land	$ 82,335us-gaap_Land	$ 84,220us-gaap_Land
Leasehold improvements	219,152us-gaap_LeaseholdImprovementsGross	208,947us-gaap_LeaseholdImprovementsGross
Premises and equipment, gross	1,314,422us-gaap_PropertyPlantAndEquipmentGross	1,261,890us-gaap_PropertyPlantAndEquipmentGross
Less: accumulated depreciation and amortization	701,438	628,370
Premises and equipment, net	612,984us-gaap_PropertyPlantAndEquipmentNet	633,520us-gaap_PropertyPlantAndEquipmentNet
Owned Assets [Member]
Property, Plant and Equipment [Line Items]
Buildings	406,522	402,065
Furniture and equipment	586,429	547,824
Less: accumulated depreciation and amortization	686,372	617,228
Capital Leases [Member]
Property, Plant and Equipment [Line Items]
Buildings	1,131	1,131
Furniture and equipment	18,853	17,703
Less: accumulated depreciation and amortization	$ 15,066	$ 11,142

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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-Name Accounting Standards Codification

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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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- 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 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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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

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

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