OTHER INTANGIBLE ASSETS AND LIABILITIES - Amortization of Acquired Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Acquired below-market lease amortization	$ 700	$ 1,590	$ 2,190
Above Market Leases
Finite-Lived Intangible Assets [Line Items]
Amortization expenses	10	63	51
Acquired in-place Leases
Finite-Lived Intangible Assets [Line Items]
Amortization expenses	$ 1,364	$ 2,112	$ 3,691