INCOME TAXES - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Assets:
Compensation related	$ 17,341	$ 12,273
Credit losses	1,269	1,994
Acquisition related		1,929
Other	407	1,270
Total deferred tax assets	19,017	17,466
Deferred Tax Liabilities:
Mark-to-market of derivatives and loans held for sale	(19,934)	(9,745)
Mortgage servicing rights related	(135,519)	(107,166)
Acquisition related	(722)
Depreciation	(1,862)	(1,980)
Total deferred tax liabilities	(158,037)	(118,891)
Deferred tax liabilities, net	$ (139,020)	$ (101,425)