LOANS RECEIVABLE AND INVESTMENTS (Details) $ in Thousands	1 Months Ended	9 Months Ended		12 Months Ended
	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($) loan	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($) loan	Aug. 31, 2015 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Marketable securities		$ 0		$ 76,046
Available-for-sale securities, unrealized gain (loss)		1,783		6,784
Secured loans, unsecured loans, and other available-for-sale securities, carrying amount		799,917		896,547
Secured loans, unsecured loans, and other available-for-sale securities, amortized cost		798,134		889,763
Secured loans, unsecured loans, and other available-for-sale securities, fair value		807,652		907,061
Investment in loans receivable and other		74,386	$ 66,436
Purchase of marketable securities		0	$ 46,689
Total proceeds from sale or maturity of marketable securities				22,300
Recognized gain on sale of marketable securities				600
Proceeds from sale of loans		97,000		55,900
Gain on the repayment of loans receivable		1,900		5,200
Secured mortgage loans and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Secured loan receivable, carrying amount and amortized cost		703,003		739,766
Mortgage loans and other, fair value		$ 709,527		$ 748,842
Number of loans sold | loan		3		3
Secured mortgage loans and other | Mezzanine Loan Investment Due 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment in loans receivable and other				$ 425,000
Secured loan receivable, interest rate				8.10%
Secured mortgage loans and other | CCP Spin-Off
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans receivable contributed in spin-off | loan					2
Loans receivable contributed in Spin-Off					$ 26,900
Loans receivable held for sale				$ 26,900
Unsecured loans receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Secured loan receivable, carrying amount and amortized cost		$ 33,210		17,620
Mortgage loans and other, fair value		$ 34,421		$ 19,058
Number of loans sold | loan		1		2
Unsecured loans receivable | CCP Spin-Off
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans receivable contributed in spin-off | loan					7
Loans receivable contributed in Spin-Off					$ 4,200
Loans receivable held for sale				$ 4,300
Secured loans receivable and investments, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Available-for-sale securities, unrealized gain (loss)		$ 1,783		1,738
Secured loans, unsecured loans, and other available-for-sale securities, carrying amount		766,707		802,881
Secured loans, unsecured loans, and other available-for-sale securities, amortized cost		764,924		801,143
Secured loans, unsecured loans, and other available-for-sale securities, fair value		773,231		811,957
Other Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Available-for-sale securities, unrealized gain (loss)		0		5,046
Secured loans, unsecured loans, and other available-for-sale securities, carrying amount		33,210		93,666
Secured loans, unsecured loans, and other available-for-sale securities, amortized cost		33,210		88,620
Secured loans, unsecured loans, and other available-for-sale securities, fair value		34,421		95,104
Government-sponsored pooled loan investments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Marketable securities		63,704		63,115
Available-for-sale securities, amortized cost		61,921		61,377
Available-for-sale securities, unrealized gain (loss)		1,783		1,738
Investment in loans receivable and other				38,700
Marketable securities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Marketable securities				76,046
Available-for-sale securities, amortized cost				71,000
Available-for-sale securities, unrealized gain (loss)				5,046
Senior unsecured corporate bonds
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value of investment	$ 71,000
Proceeds from sale of investment	$ 76,800
Recognized gain on sale of investments		5,800
Unrealized gains of investments		$ 5,000
Purchase of marketable securities				71,000
Marketable equity securities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchase of marketable securities				$ 21,700