Supplemental Equity and Comprehensive Income Information (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2011	Jun. 30, 2011	Mar. 31, 2011 Winterthur Technologie AG	Jun. 30, 2011 Winterthur Technologie AG	Dec. 31, 2011 Winterthur Technologie AG
Business Acquisitions Information
Percentage of subsidiary shares owned by entity on the business acquisition date (as a percent)			86.00%
Percentage of subsidiary shares owned by entity as of balance sheet date (as a percent)				98.00%	100.00%
Cash paid for purchase and sale of subsidiary shares - net	$ 9	$ 42		$ 50
Business combination allocation to noncontrolling interest		$ 56	$ 56

The cash outflow or inflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity). Also includes the cash inflow related to the sale of subsidiary shares. These items are presented net.

No definition available.

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company as of the balance sheet date.

+ References

No definition available.

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- Details

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- Definition

Increase in noncontrolling interest balance because of a business combination that occurred during the period.

+ References

No definition available.

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section H

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