Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Common Stock, Par Value (in Dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	750,000,000	750,000,000
Common Stock, Shares Issued	406,939,830	406,423,514
Common Stock, Shares Outstanding	406,939,830	406,423,514
Total [Member]
Operating real estate, accumulated depreciation (in Dollars)	$ 1,660,635	$ 1,549,380
Preferred Stock [Member]
Preferred Stock, Par Value (in Dollars per share)	$ 1.00	$ 1.00
Preferred Stock, Shares Authorized	3,092,000	3,092,000
Series F Preferred Stock [Member]
Preferred Stock, Par Value (in Dollars per share)	$ 1.00	$ 1.00
Preferred Stock, Shares Authorized	700,000	700,000
Preferred Stock, Shares Issued	700,000	700,000
Preferred Stock, Shares Outstanding	700,000	700,000
Preferred Stock, Aggregate Liquidation Preference (in Dollars per share)	$ 175,000,000	$ 175,000,000
Series G Preferred Stock [Member]
Preferred Stock, Par Value (in Dollars per share)	$ 1.00	$ 1.00
Preferred Stock, Shares Authorized	184,000	184,000
Preferred Stock, Shares Issued	184,000	184,000
Preferred Stock, Shares Outstanding	184,000	184,000
Preferred Stock, Aggregate Liquidation Preference (in Dollars per share)	$ 460,000,000	$ 460,000,000
Series H Preferred Stock [Member]
Preferred Stock, Par Value (in Dollars per share)	$ 1.00	$ 1.00
Preferred Stock, Shares Authorized	70,000	70,000
Preferred Stock, Shares Issued	70,000	70,000
Preferred Stock, Shares Outstanding	70,000	70,000
Preferred Stock, Aggregate Liquidation Preference (in Dollars per share)	$ 175,000,000	$ 175,000,000