BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Fixed lease income - operating leases	$ 41,910	$ 44,342	$ 83,843	$ 88,084
Variable lease income - operating leases	1,302	1,548	3,082	2,632
Revenues	43,910	46,934	88,316	92,542
Other Property Revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 698	$ 1,044	$ 1,391	$ 1,826