Supplemental Cash Flow (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Changes in Operating Capital [Abstract]
Decrease in accounts receivable	$ 796.5	$ 729.6
Increase in work in process and other current assets	(163.6)	(203.1)
Decrease in accounts payable	(932.2)	(971.9)
Decrease in customer advances and other current liabilities	10.9	(70.8)
Change in other assets and liabilities, net	(22.6)	163.6
Change in operating capital	(311.0)	(352.6)
Income taxes paid	123.0	86.7
Interest paid	$ 41.1	$ 49.3

Decrease in customer advances and other current liabilities

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- Definition

(Increase) decrease in work in progress and other current assets

+ References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

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- Definition

Change in recurring obligations of a business that arise from the acquisition of merchandise, materials, supplies and services used in the production and sale of goods and services.

+ References

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-Publisher FASB

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-Number 95

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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The increase (decrease) during the reporting period in other assets used in operating activities less other operating liabilities used in operating activities not separately disclosed in the statement of cash flows. May include changes in other current assets and liabilities, other noncurrent assets and liabilities, or a combination of other current and noncurrent assets and liabilities.

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- Definition

The amount of cash paid for interest during the period.

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