SEGMENT DISCLOSURE (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) item	Jun. 30, 2014 USD ($)
Segment disclosure
Number of types of commercial real estate properties | item			3
Revenues	$ 66,919	$ 65,187	$ 134,158	$ 127,784
Property expenses:
General and administrative	1,955	2,357	4,547	3,131
EXPENSES	65,921	61,017	133,390	118,248
Reportable segments
Property expenses:
Total segment net operating income	33,693	34,582	67,786	67,215
Reportable segments | Office
Segment disclosure
Revenues	47,084	45,181	93,699	88,455
Property expenses:
Operating	20,060	17,933	39,451	35,586
General and administrative	113	76	426	392
EXPENSES	20,173	18,009	39,877	35,978
Total segment net operating income	26,911	27,172	53,822	52,477
Reportable segments | Hotel
Segment disclosure
Revenues	15,822	14,798	31,541	29,137
Property expenses:
Operating	9,987	9,923	20,664	19,769
General and administrative	38	36	79	73
EXPENSES	10,025	9,959	20,743	19,842
Total segment net operating income	5,797	4,839	10,798	9,295
Reportable segments | Multi-family
Segment disclosure
Revenues	4,013	5,208	8,918	10,192
Property expenses:
Operating	2,938	2,583	5,579	4,670
General and administrative	90	54	173	79
EXPENSES	3,028	2,637	5,752	4,749
Total segment net operating income	$ 985	$ 2,571	$ 3,166	$ 5,443