Earnings/(Loss) Per Share (Details) (USD $) In Thousands, except Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Numerator for earnings per share - basic and diluted:
Net loss attributable to common stockholders	$ (15,559)	$ (26,134)	$ (33,653)	$ (81,537)
Denominator for earnings per share - basic and diluted:
Weighted average common shares outstanding	215,066,000	167,056,000	197,010,000	162,294,000
Non-vested restricted stock awards	(1,250,000)	(1,653,000)	(1,287,000)	(1,453,000)
Denominator for basic and diluted earnings per share	213,816,000	165,403,000	195,723,000	160,841,000
Net loss attributable to common stockholders	$ (0.07)	$ (0.16)	$ (0.17)	$ (0.51)
Operating Partnership Units [Member]
Loss Per Share (Textual) [Abstract]
Antidilutive securities excluded from computation of earnings per share amount	8,235,068	5,615,619	6,987,415	5,850,432
Convertible Preferred Stock [Member]
Loss Per Share (Textual) [Abstract]
Antidilutive securities excluded from computation of earnings per share amount	3,035,548	3,035,548	3,035,548	3,035,548
Stock Compensation Plan [Member]
Loss Per Share (Textual) [Abstract]
Antidilutive securities excluded from computation of earnings per share amount	2,156,175	2,425,654	2,107,783	2,209,025

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

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+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details