DISCONTINUED OPERATIONS - Effect on Net Income from Properties Classified as Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
REVENUE	$ 45,608	$ 43,035
EXPENSES
Property operating expenses, excluding real estate taxes	14,804	14,246
Real estate taxes	5,232	5,021
Depreciation and amortization	18,111	20,516
General and administrative expenses	3,806	3,619
TOTAL EXPENSES	44,148	44,829
Interest expense	(7,896)	(8,296)
Other income	17	16
Gain (loss) on sale of discontinued operations	54	16,036
INCOME (LOSS) FROM DISCONTINUED OPERATIONS	0	13,882
Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
REVENUE	0	196
EXPENSES
Property operating expenses, excluding real estate taxes	0	7
Real estate taxes	0	35
Depreciation and amortization	0	2
General and administrative expenses	0	5
TOTAL EXPENSES	0	49
Operating income (loss)	0	147
Interest expense	0	(1)
Other income	0	4
Income (loss) from discontinued operations before gain (loss) on sale of discontinued operations	0	150
Gain (loss) on sale of discontinued operations	0	13,732
INCOME (LOSS) FROM DISCONTINUED OPERATIONS	$ 0	$ 13,882