Supplemental Equity and Comprehensive Income Information (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2011	Dec. 31, 2011
Business Acquisitions Information
Cash paid for purchase and sale of subsidiary shares - net		$ 49
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)		100.00%
Cash paid for purchase and sale of subsidiary shares - net		$ 57

The cash outflow 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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