INVESTMENTS IN RESIDENTIAL MORTGAGE LOANS - Summary of Activities Related to the Valuation Allowance on Reverse Mortgage Loans and Allowance for Loan Losses on Performing Loans (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($)
Reverse Mortgage Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning, balance	$ 1,518
Provision for loan losses	245	[1]
Charge-offs	0	[2]
Ending, balance	1,763
Performing Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning, balance	1,447
Provision for loan losses	118	[1]
Charge-offs	(1,371)	[2]
Ending, balance	$ 194

[1] Based on an analysis of collective borrower performance, credit ratings of borrowers, loan-to-value ratios, estimated value of the underlying collateral, key terms of the loans and historical and anticipated trends in defaults and loss severities at a pool level.

[2] Loans, other than PCI loans, are generally charged off or charged down to the net realizable value of the collateral (i.e., fair value less costs to sell), with an offset to the allowance for loan losses, when available information confirms that loans are uncollectible.