PREMISES AND EQUIPMENT (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Buildings and Improvements	$ 138,686	$ 135,263
Leasehold Improvements	82,034	56,530
Furniture and equipment	224,623	146,835
Property, Plant and Equipment, Gross	445,343	338,628
Accumulated Depreciation	(318,659)	(228,712)
Subtotal	126,684	109,916
Land	23,873	22,939
Projects in progress	7,652	17,134
Premises and equipment, net	$ 158,209	$ 149,989
Minimum [Member] \| Building Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Minimum [Member] \| Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	1 year
Minimum [Member] \| Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years
Maximum [Member] \| Building Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	35 years
Maximum [Member] \| Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Maximum [Member] \| Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years

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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