PREMISES AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	$ 75,328	$ 181,187
Less: Accumulated depreciation and amortization	(63,434)	(156,661)
Total	11,894	24,526
Depreciation and amortization expense	14,890	18,509	$ 30,799
Computer hardware and software
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	52,837	144,608
Leasehold improvements
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	14,792	23,800
Furniture and fixtures
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	5,882	8,775
Office equipment and other
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	$ 1,817	$ 4,004

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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.

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