PREMISES AND EQUIPMENT (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Buildings and Improvements	$ 131,206	$ 132,008
Leasehold Improvements	54,734	53,866
Furniture and equipment	176,116	166,853
Property, Plant and Equipment, Gross	362,056	352,727
Accumulated Depreciation	(256,355)	(245,777)
Subtotal	105,701	106,950
Land	24,640	24,640
Projects in progress	17,473	10,305
Premises and equipment, net	$ 147,814	$ 141,895
Maximum [Member] \| FurnitureAndFixturesMember
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Maximum [Member] \| BuildingImprovementsMember
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	35 years
Maximum [Member] \| LeaseholdImprovementsMember
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Minimum [Member] \| FurnitureAndFixturesMember
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years
Minimum [Member] \| BuildingImprovementsMember
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Minimum [Member] \| LeaseholdImprovementsMember
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	1 year

Total Property

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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 of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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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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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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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