FAIR VALUE MEASUREMENTS (Impairment Charges) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of real estate assets	$ 15,983	$ 57,163
Land
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of real estate assets	3,595	10,006
Buildings, fixtures and improvements
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of real estate assets	11,737	44,249
Intangible lease assets
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of real estate assets	696	3,159
Intangible lease liabilities
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of intangible lease liability	$ (45)	$ (251)