Acquisition Pro Forma Results (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2012
Business Acquisition, Pro Forma Information [Abstract]
Revenues	$ 3,107.4
Income from Continuing Operations	295.4
Net Income	$ 291.9
Earnings per Share from Continuing Operations:
Basic (in dollars per share)	$ 0.80
Diluted (in dollars per share)	$ 0.80
Earnings per Share:
Basic (in dollars per share)	$ 0.79
Diluted (in dollars per share)	$ 0.79

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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.

+ References

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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