SEGMENT REPORTING - Capital Expenditures (Details) ft² in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015 USD ($) ft² unit	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) ft² unit	Sep. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Capital expenditures	[1]	$ 26,888	$ 34,793	$ 118,398	$ 97,682
Lloyd District Portfolio - Phase I
Segment Reporting Information [Line Items]
Number of units in real estate property | unit		657		657
Net rentable area | ft²		47		47
Mixed-Use
Segment Reporting Information [Line Items]
Capital expenditures	[1]	$ 50	445	$ 587	3,382
Multifamily
Segment Reporting Information [Line Items]
Capital expenditures	[1],[2]	16,678	25,007	75,374	66,647
Office
Segment Reporting Information [Line Items]
Capital expenditures	[1]	7,616	7,247	37,202	22,928
Retail
Segment Reporting Information [Line Items]
Capital expenditures	[1]	$ 2,544	$ 2,094	$ 5,235	$ 4,725

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

[2] Multifamily capital expenditures include all capital expenditures incurred for the new development project Lloyd District Portfolio - Phase I, which consists of 657 multifamily units and approximately 47,000 square feet of retail space.