PREMISES AND EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	$ 234,985		$ 234,985		$ 232,870
Less: Accumulated depreciation and amortization	(154,162)		(154,162)		(129,397)
Total	80,823		80,823		103,473
Depreciation and amortization expense	8,500	$ 9,200	27,411	$ 27,521
Computer hardware and software
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	175,512		175,512		164,877
Office equipment and other
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	12,077		12,077		20,188
Furniture and fixtures
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	13,826		13,826		13,997
Leasehold improvements
PREMISES AND EQUIPMENT, NET
Premises and equipment, gross	$ 33,570		$ 33,570		$ 33,808