MORTGAGE LOAN RECEIVABLES - Provision for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Loan and Lease Losses [Roll Forward]
Provision for loan losses at beginning of period	$ 3,100	$ 2,500	$ 1,900
Provision for loan losses	600	600	600
Provision for loan losses at end of period	$ 3,700	$ 3,100	$ 2,500