PREMISES AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	$ 232,693	$ 236,464
Less: Accumulated depreciation and amortization	(187,062)	(163,191)
Total	45,631	73,273
Depreciation and amortization expense	30,799	36,447	$ 36,788
Computer hardware and software
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	182,215	179,567
Office equipment and other
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	7,384	9,388
Furniture and fixtures
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	13,313	14,092
Leasehold improvements
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	$ 29,781	$ 33,417

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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