BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Loans Receivable (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2015	Mar. 11, 2014
Loans receivable
Net impairment (recovery)	$ 137	$ (3)	$ 149	$ (239)
Commercial mortgage loans
Loans receivable
Unamortized acquisition discounts related to sold loans					$ 15,951
PMC Commercial
Loans receivable
Discount on acquisition						$ 33,907
Acquisition discount	$ 1,455		$ 1,455