Archstone Acquisition (Details) (USD $)	3 Months Ended		9 Months Ended		0 Months Ended	7 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Feb. 27, 2013 Archstone	Sep. 30, 2013 Archstone		Sep. 30, 2013 Archstone	Feb. 27, 2013 Archstone Equity
Archstone acquisition
Percentage of assets and liabilities acquired					40.00%				60.00%
Acquisition related expenses recognized								$ 82,544,000
Acquisition related expenses reported as a component of equity in income (loss) of unconsolidated entities	130,592,000	3,260,000	143,527,000	(16,244,000)				37,295,000
Consideration
Number of shares issued					14,889,706			14,889,706
Value of shares issued					1,875,210,000
Cash payment					760,000,000
Fair value of indebtedness assumed					3,732,980,000
Principal amount of consolidated indebtedness					3,512,202,000	3,512,202,000		3,512,202,000
Debt fair value exceeds the principal face value					220,777,000
Debt fair value exceeds the principal face value relating to debt repaid					70,479,000
Redemption value of preferred equity					67,500,000	67,500,000		67,500,000
Information for acquisition that is included in condensed consolidated statement of operations comprehensive income from the acquisition date
Revenues	430,525,000	389,189,000	1,244,407,000	1,068,752,000		246,969,000
Income (Loss) attributable to common shareholders	241,100,000	(10,715,000)	540,929,000	100,929,000		(128,542,000)	[1]
Supplemental consolidated pro forma information
Revenues				1,152,418,000
Income from continuing operations				$ 242,647,000
Earnings per common share - diluted (from continuing operations) (in dollars per share)				$ 1.87

[1] Amounts exclude acquisition costs for the Archstone Acquisition.