SEGMENT REPORTING - Operating Activity Within Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ 20,062	$ 28,848
Total segments’ profit	54,386	63,130
Office
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	44,464	44,509
Property Expenses	(11,364)	(11,793)
Operating Income (Loss)	33,100	32,716
Retail
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	21,774	25,826
Property Expenses	(7,442)	(7,331)
Operating Income (Loss)	14,332	18,495
Multifamily
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	12,552	12,825
Property Expenses	(5,491)	(5,510)
Operating Income (Loss)	7,061	7,315
Mixed-use
Segment Reporting Information [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	5,196	13,583
Property Expenses	(5,303)	(8,979)
Operating Income (Loss)	$ (107)	$ 4,604