SEGMENT DISCLOSURE - Operating Income (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) property	Sep. 30, 2017 USD ($) property	Sep. 30, 2018 USD ($) property	Sep. 30, 2017 USD ($) property
Segment Reporting [Abstract]
Number of types of commercial real estate properties | property	2	3	2	3
Segment disclosure
Revenues	$ 47,640	$ 55,384	$ 147,597	$ 183,632
Expenses:
General and administrative	1,205	1,342	6,496	4,668
Interest expense	6,965	9,359	20,409	28,645
EXPENSES	48,054	57,369	144,760	203,473
Segment net operating income	25,332	27,899	82,909	102,483
Office
Segment disclosure
Revenues	36,473	41,427	109,293	134,434
Expenses:
Operating	14,492	18,761	39,922	50,318
General and administrative	83	106	1,062	788
EXPENSES	14,575	18,867	40,984	51,106
Segment net operating income	21,898	22,560	68,309	83,328
Hotel
Segment disclosure
Revenues	8,542	8,406	29,980	29,528
Expenses:
Operating	5,946	5,943	19,316	18,968
General and administrative	0	30	18	69
EXPENSES	5,946	5,973	19,334	19,037
Segment net operating income	2,596	2,433	10,646	10,491
Multifamily
Segment disclosure
Revenues	0	2,683	0	12,400
Expenses:
Operating	0	1,354	0	6,981
General and administrative	0	36	0	378
EXPENSES	0	1,390	0	7,359
Segment net operating income	0	1,293	0	5,041
Lending
Segment disclosure
Revenues	2,625	2,868	8,324	7,270
Expenses:
General and administrative	414	294	1,273	971
Interest expense	633	116	1,117	203
Fees to related party	740	845	1,980	2,473
EXPENSES	1,787	1,255	4,370	3,647
Segment net operating income	$ 838	$ 1,613	$ 3,954	$ 3,623