Acquisitions And Divestitures (Details) (USD $) In Millions, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Proforma information for the Company as if the acquisition of properties
Revenues and Other	$ 3,534	$ 6,795
Net Income	937	1,730
Preferred Stock Dividends	19	38
Income Attributable to Common Stock	$ 918	$ 1,692
Net Income per Common Share - Basic	$ 2.41	$ 4.44
Net Income per Common Share - Diluted	$ 2.36	$ 4.36

Business Acquisition Pro Forma Net Income Loss Available To Common Stockholder Basic.

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Business Acquisition Pro Forma Preferred Stock Dividends.

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Pro forma basic earnings per share or earnings per unit, which is commonly presented in initial public offerings based on the terms of the offering.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 11
-Section 02
-Paragraph b
-Subparagraph 7

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Pro forma diluted earnings per share, which is commonly presented in initial public offerings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 11
-Section 02
-Paragraph b
-Subparagraph 7

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