Equity (Details Textuals 1) (USD $) In Millions, except Share data	3 Months Ended
Mar. 31, 2011
Equity - Common Stock (Textuals) [Abstract]
Shares of common stock, issuance date	March 8, 2011
Common stock, shares issued	68,570,000
Price per share of common stock issued	$ 43.25
Proceeds from issuance of common stock	$ 2,966
Issuance costs	$ 16

The date common stock was issued.

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- Definition

The dollar amount received for each share of common stock issued in the stock transaction.

+ Details

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- Definition

Equity common stock textuals.

+ Details

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18, 19, 20

+ Details

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 18

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 19
-Subparagraph a

+ Details

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- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

+ Details

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