Summary of Significant Accounting Policies (Basic and Diluted Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net Income (Loss) Available to Common Stockholders, Basic	$ (126,145)	$ 31,416	$ (14,108)
Participating Securities, Distributed and Undistributed Earnings	(3,075)	(3,243)	(2,513)
Net Income Loss Attributable To Common Stockholders Basic	(129,220)	28,173	(16,621)
Net Income (Loss) Attributable to Noncontrolling Interest, Operating Partnerships	0	859	0
Net Income (Loss) Available to Common Stockholders, Diluted	(129,220)	29,032	(16,621)
Weighted Average Number of Shares Outstanding, Basic	267,900	252,694	238,920
Weighted Average Limited Partnership Units Outstanding, Basic	0	6,904	0
Weighted Average Number Diluted Shares Outstanding Adjustment	0	0	0
Weighted Average Number of Shares Outstanding, Diluted	267,900	259,598	238,920
Subsidiary of Common Parent [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net Income (Loss) Available to Common Stockholders, Basic	(128,418)	32,275	(14,459)
Participating Securities, Distributed and Undistributed Earnings	(3,075)	(3,243)	(2,513)
Net Income Loss Attributable To Common Stockholders Basic	$ (131,493)	$ 29,032	$ (16,972)
Weighted Average Number of Shares Outstanding, Basic	272,729	259,598	244,870
Weighted Average Number of Shares Outstanding, Diluted	272,729	259,598	244,870