Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			1 Months Ended	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013 Loan	Jan. 31, 2013 Marcus and Millichamp Company TMMC Affiliate [Member]	Sep. 30, 2013 MMC [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	$ 2.6	$ 2.8
Related Party Transaction [Line Items]
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					0.4
Preferred equity interest investment in a related party entity				8.6
Notes to affiliates which have been repaid			2
Notes to affiliates outstanding			2
Short term bridge loan			$ 56.8