SEGMENT DISCLOSURE - Assets and Capital Expenditures and Loan Originations (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Segment disclosure
Total assets	$ 1,391,715		$ 1,336,388
Total capital expenditures	12,805	$ 23,237
Loan originations	53,320	49,532
Total capital expenditures and loan originations	66,125	72,769
Reportable segments | Office
Segment disclosure
Total assets	1,109,090		997,808
Total capital expenditures	11,462	22,632
Reportable segments | Hotel
Segment disclosure
Total assets	108,884		107,790
Total capital expenditures	1,343	267
Reportable segments | Lending
Segment disclosure
Total assets	94,454		92,919
Reportable segments | Multifamily
Segment disclosure
Total assets	0		815
Total capital expenditures	0	$ 338
Non-segment
Segment disclosure
Total assets	$ 79,287		$ 137,056