Related Party Transactions (Details) $ in Thousands	1 Months Ended		3 Months Ended			6 Months Ended
	Jun. 30, 2015 USD ($) apartment	Jul. 31, 2014 USD ($) apartment	Jun. 30, 2015 USD ($) apartment	Mar. 31, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) apartment	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Related Party Transaction [Line Items]
Management and other fees from affiliates			$ 3,600		$ 5,000	$ 9,300	$ 7,600
Development and redevelopment fees			$ 1,500		$ 2,200	4,600	3,100
Company's share of gain on the sales of co-investment						(469)	(3,211)
Payments to acquire preferred equity investments	$ 1,300					$ 97,512	$ 58,029
Apartment units owned | apartment	58,768		58,768			58,768
Notes and other receivables	$ 25,676		$ 25,676			$ 25,676		$ 24,923
Notes Receivable [Member]
Related Party Transaction [Line Items]
Notes and other receivables	$ 4,109		$ 4,109			$ 4,109		$ 8,105
Anaheim, CA Multifamily Property [Member]
Related Party Transaction [Line Items]
Preferred equity investments				$ 13,700
Preferred stock, stated interest percentage	9.00%
Company's share of gain on the sales of co-investment				$ 13,700
Limited Liability Company [Member] | Greentree Apartments [Member]
Related Party Transaction [Line Items]
Preferred stock, stated interest percentage	9.50%
Payments to acquire preferred equity investments	$ 10,000
Apartment units owned | apartment	220		220			220
Limited Liability Company [Member] | Sterling Cove [Member]
Related Party Transaction [Line Items]
Preferred stock, stated interest percentage	9.50%
Payments to acquire preferred equity investments	$ 5,000
Apartment units owned | apartment	218		218			218
Paragon Apartments [Member]
Related Party Transaction [Line Items]
Number of units | apartment		301
Cash consideration for BRE merger		$ 111,000