Equity of the Parent Company (Dividends and Distributions) (Details) (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jul. 15, 2011	Apr. 15, 2011	Jun. 30, 2011
Dividends and Distributions Declared			$ 62,174
Series A Preferred Stock [Member]
Declaration Date	Jun. 15, 2011	Mar. 14, 2011
Amount Per Share/Unit	$ 0.46094	$ 0.46094
Dividend and Distribution Payable Date	Jul. 15, 2011	Apr. 15, 2011
Dividend and Distribution Amount	4,241	4,240
Dividends and Distributions Declared			8,481
Common stock and OP units [Member]
Declaration Date	Jun. 15, 2011	Mar. 14, 2011
Amount Per Share/Unit	$ 0.20000	$ 0.20000
Dividend and Distribution Payable Date	Jul. 15, 2011	Apr. 15, 2011
Dividend and Distribution Amount	26,847	26,846
Dividends and Distributions Declared			$ 53,693

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 01-6
-Paragraph 14
-Subparagraph l
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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