PREMISES AND EQUIPMENT (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment, Net [Abstract]
Premises and equipment, gross	$ 297,920	$ 247,549
Accumulated depreciation	(133,282)	(127,561)
Premises and equipment, net	164,638	119,988
Land and Land Improvements [Member]
Property, Plant and Equipment, Net [Abstract]
Premises and equipment, gross	26,301	24,340
Bank Premises [Member]
Property, Plant and Equipment, Net [Abstract]
Premises and equipment, gross	141,905	133,259
Equipment and Construction in Progress [Member]
Property, Plant and Equipment, Net [Abstract]
Premises and equipment, gross	89,819	89,950
Operating Lease Right-of-Use Assets [Member]
Property, Plant and Equipment, Net [Abstract]
Premises and equipment, gross	$ 39,895	$ 0

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, 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

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