SEGMENT REPORTING - Capital Expenditures (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Capital expenditures	[1]	$ 8,155	$ 17,752
Retail
Segment Reporting Information [Line Items]
Capital expenditures	[1]	1,246	5,414
Office
Segment Reporting Information [Line Items]
Capital expenditures	[1]	6,360	10,929
Multifamily
Segment Reporting Information [Line Items]
Capital expenditures	[1],[2]	459	1,344
Mixed-Use
Segment Reporting Information [Line Items]
Capital expenditures	[1]	$ 90	$ 65

[1] Capital expenditures represent cash paid for capital expenditures during the period and include leasing commissions paid

[2] d