PREMISES AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 69,662		$ 69,662		$ 75,328
Less: Accumulated depreciation and amortization	(59,466)		(59,466)		(63,434)
Total	10,196		10,196		11,894
Depreciation and amortization	1,200	$ 3,600	2,335	$ 7,701
Computer hardware and software
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	52,458		52,458		52,837
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	10,760		10,760		14,792
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	5,251		5,251		5,882
Office equipment and other
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 1,193		$ 1,193		$ 1,817