Related Party Transactions (Details) (USD $)	3 Months Ended		6 Months Ended				1 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2014 Loan	Jun. 30, 2013	Jun. 30, 2014 Loan	Jun. 30, 2013	Dec. 31, 2013 Loan	Jun. 30, 2014 Canada Pension Plan Investment Board (CPPIB) I [Member]	Jan. 31, 2013 Marcus and Millichamp Company TMMC Affiliate [Member]	Sep. 30, 2013 MMC [Member]	Jul. 31, 2014 Paragon Apartments [Member] Unit	Jun. 30, 2014 Reduction to general and administrative expenses [Member]	Jun. 30, 2013 Reduction to general and administrative expenses [Member]	Jun. 30, 2014 Reduction to general and administrative expenses [Member]	Jun. 30, 2013 Reduction to general and administrative expenses [Member]
Related Party Transactions [Abstract]
Management and other fees from affiliates including management, property management, development and redevelopment fees from co-investments, net of intercompany amounts eliminated by company	$ 5,000,000	$ 3,200,000	$ 7,600,000	$ 6,000,000						$ 2,200,000	$ 1,200,000	$ 3,100,000	$ 2,100,000
Related Party Transaction [Line Items]
Management and other fees from affiliates including management, property management, development and redevelopment fees from co-investments, net of intercompany amounts eliminated by company	5,000,000	3,200,000	7,600,000	6,000,000						2,200,000	1,200,000	3,100,000	2,100,000
Preferred return on preferred equity investment, thereafter, maximum (in hundredths)								13.00%
Preferred return on preferred equity investment, thereafter, minimum (in hundredths)								9.00%
Maximum Term Extended (in years)								1 year
Income related to the restructured investment								400,000
Preferred equity interest investment in a related party entity							8,600,000
Notes to affiliates which have been repaid					2
Notes to affiliates outstanding					2
Short term bridge loan					56,800,000
Number of units									301
Cost of acquired entity			555,826,000	0					111,000,000
Number of loans outstanding	1		1
Notes receivable	$ 66,522,000		$ 66,522,000		$ 68,255,000	$ 19,800,000