SEGMENT REPORTING Capital Expenditures (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2012
Segment Reporting Information [Line Items]
Capital Expenditures	$ 34,793	[1]	$ 12,932	[1]	$ 97,682	[1]	$ 35,480	[1]
Total Retail
Segment Reporting Information [Line Items]
Capital Expenditures	2,094	[1]	616	[1]	4,725	[1]	3,143	[1]
Total Office
Segment Reporting Information [Line Items]
Capital Expenditures	7,247	[1]	6,785	[1]	22,928	[1]	20,674	[1]
Total Multifamily
Segment Reporting Information [Line Items]
Capital Expenditures	25,007	[1]	5,256	[1]	66,647	[1]	11,017	[1]
Total Mixed-Use
Segment Reporting Information [Line Items]
Capital Expenditures	$ 445	[1]	$ 275	[1]	$ 3,382	[1]	$ 646	[1]

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