Equity - Common Stock (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Common Stock [Details]
Common shares, authorized	500		500		500
Common shares, outstanding	295		295		293
Total issuances - shares	0.4	5.4	1.4	11.5
Issuance through 401(k) and or IPP - shares	0	5.4	0	10.7
Total issuances - net proceeds	$ 18	$ 208	$ 26	$ 405
Issuances through 401(k) and or IPP - net proceeds	$ 0	$ 208	$ 1	$ 405

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Total number of common shares issued to meet share delivery obligations under benefit plans and stock purchase plans.

+ Details

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury) during the reporting period. These shares represent capital invested by the firm's shareholders and owners.

+ Details

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- Definition

Value of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury) during the reporting period. These amounts represent capital invested by the firm's shareholders and owners net of expenses incurred.

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- Definition

Value of common shares issued for the period to meet share delivery obligations under benefit plans and stock purchase plans net of expenses incurred.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 30
-Article 5

+ Details

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- Definition

Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Excludes common shares repurchased by the entity and held as Treasury shares. Shares outstanding equals shares issued minus shares held in treasury. Does not include common shares that have been repurchased.

+ 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 30
-Article 5

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