SUBSEQUENT EVENTS (Details) $ in Thousands	1 Months Ended	9 Months Ended
	Oct. 31, 2015 USD ($) derivative	Sep. 30, 2015 USD ($)
Fund IV
Subsequent Event [Line Items]
Consideration transferred		$ 84,036
Warwick, RI | Fund IV | Bald Hill Road | Subsequent Event
Subsequent Event [Line Items]
Percentage of interests acquired	90.00%
Consideration transferred	$ 8,300
Notes receivable converted into equity	$ 6,500
San Francisco, CA | Fund IV | Fillmore Street | Subsequent Event
Subsequent Event [Line Items]
Percentage of interests acquired	90.00%
Consideration transferred	$ 7,700
Forward Contracts | Subsequent Event
Subsequent Event [Line Items]
Derivative, number of instruments held | derivative	2
Notional amount	$ 100,000
Basis spread on variable rate	1.30%