PREMISES AND EQUIPMENT: (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment, Gross [Abstract]
Land	$ 11,353us-gaap_Land	$ 11,423us-gaap_Land
Building and leasehold improvements	55,074us-gaap_BuildingsAndImprovementsGross	54,353us-gaap_BuildingsAndImprovementsGross
Furniture and equipment	45,602thff_FurnitureAndEquipment	42,546thff_FurnitureAndEquipment
Property Plant And Equipment Gross	112,029us-gaap_PropertyPlantAndEquipmentGross	108,322us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation	(60,227)	(56,873)
TOTAL	$ 51,802us-gaap_PropertyPlantAndEquipmentNet	$ 51,449us-gaap_PropertyPlantAndEquipmentNet

Fixed asset of the company

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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- Definition

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.

+ References

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

+ References

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- Definition

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.

+ References

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

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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

-Publisher FASB

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