FAIR VALUE DISCLOSURES - Summary of Face Values, Carrying Amounts and Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans receivable, Face Value	$ 54,029	$ 53,484
Preferred equity investment, Face Value	46,079	44,882
Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities, Face Value	700,000	700,000
Mortgage indebtedness [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities, Face Value	162,762	163,638
Carrying Amount [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans receivable	54,134	53,596
Preferred equity investments	46,451	45,190
Carrying Amount [Member] | Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	688,879	688,246
Carrying Amount [Member] | Mortgage indebtedness [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	159,905	160,752
Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans receivable	50,069	51,914
Preferred equity investments	47,363	48,332
Fair Value [Member] | Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	707,500	709,500
Fair Value [Member] | Mortgage indebtedness [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	$ 149,270	$ 150,091