Acquisition Pro Forma Results (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Business Acquisition, Pro Forma Information [Abstract]
Revenues	$ 3,122.6	$ 3,053.5	$ 9,383.7	$ 9,158.5
Income from Continuing Operations	318.8	289.0	920.6	816.9
Net Income	309.8	288.1	849.5	1,127.0
Earnings per Share from Continuing Operations:
Basic (in dollars per share)	$ 0.88	$ 0.76	$ 2.52	$ 2.12
Diluted (in dollars per share)	$ 0.87	$ 0.75	$ 2.50	$ 2.09
Earnings per Share:
Basic (in dollars per share)	$ 0.85	$ 0.75	$ 2.32	$ 2.93
Diluted (in dollars per share)	$ 0.85	$ 0.75	$ 2.31	$ 2.89
Non-recurring Pro Forma Adjustments, Cost of Revenue
Business Acquisition, Pro Forma Information [Abstract]
Net Income		24.4		39.0
Non-recurring Pro Forma Adjustments, Monetized Equity Awards
Business Acquisition, Pro Forma Information [Abstract]
Net Income				21.6
Non-recurring Pro Forma Adjustments, Transaction Costs
Business Acquisition, Pro Forma Information [Abstract]
Net Income	$ 12.8	$ 17.7	$ 15.0	$ 80.6

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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