INVESTMENTS IN RESIDENTIAL MORTGAGE LOANS - Summary of Activities Related to the Carrying Value of Reverse Mortgage Loans and Performing Loans and PCD Loans Held-for-Investment (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014
Movement in Mortgage Loans on Real Estate [Roll Forward]
Transfer of loans to real estate owned		$ (35,322)
Reverse Mortgage Loans [Member]
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance, beginning		24,965	$ 33,539
Purchases/additional fundings		988	0
Proceeds from repayments		(687)	(2,810)
Accretion of loan discount and other amortization	[1]	5,904	6,501
Provision for loan losses		(35)	(1,111)
Transfer of loans to other assets		(11,574)	(10,261)
Transfer of loans to real estate owned		(1)	(947)
Transfer of loans to held-for-sale			0
Reversal of valuation provision on loans transferred to other assets			54
Balance, ending		19,560	24,965
Performing Loans [Member]
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance, beginning		22,873	0
Purchases/additional fundings		0	134,818
Proceeds from repayments		(2,918)	(10,381)
Accretion of loan discount and other amortization	[1]	52	2,994
Provision for loan losses		(43)	(651)
Transfer of loans to other assets		0	0
Transfer of loans to real estate owned		0	0
Transfer of loans to held-for-sale			(103,907)
Reversal of valuation provision on loans transferred to other assets			0
Balance, ending		19,964	22,873
PCD Loans [Member]
Movement in Mortgage Loans on Real Estate [Roll Forward]
Balance, beginning		0	0
Purchases/additional fundings		289,664	749,739
Sales		0	0
Proceeds from repayments		0	(20,431)
Accretion of loan discount and other amortization		990	30,361
Transfer of loans to real estate owned		0	(21,842)
Transfer of loans to held-for-sale			(737,827)
Balance, ending		$ 290,654	$ 0

[1] Includes accelerated accretion of discount on loans paid in full and on loans transferred to other assets.