FAIR VALUES OF FINANCIAL INSTRUMENTS (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Assets:
Unsecured loans receivable, net	$ 22,898	$ 38,542
Liabilities:
Redeemable OP unitholder interests	119,500	111,600
Carrying Amount
Assets:
Cash and cash equivalents	64,595	94,816
Secured loans receivable, net	344,948	354,775
Unsecured loans receivable, net	22,898	38,542
Marketable securities	88,662	21,454
Liabilities:
Senior notes payable and other debt, gross	10,450,864	9,320,477
Derivative instruments and other liabilities	4,238	11,105
Redeemable OP unitholder interests	119,537	111,607
Fair Value
Assets:
Cash and cash equivalents	64,595	94,816
Secured loans receivable, net	355,559	355,223
Unsecured loans receivable, net	23,333	40,473
Marketable securities	88,662	21,454
Liabilities:
Senior notes payable and other debt, gross	10,761,254	9,405,259
Derivative instruments and other liabilities	4,238	11,105
Redeemable OP unitholder interests	$ 119,537	$ 111,607