Fair Value Measurements (Changes In The Fair Value Of Contingent Consideration Obligations) (Details) (USD $) In Millions	9 Months Ended
	Sep. 30, 2011
Fair Value Measurements
Balance as of January 1, 2011	$ 20.1
Liabilities recognized at acquisition date	1.1
(Gains) recognized in earnings	(0.5)
Payments	(5.0)
Balance as of September 30, 2011	$ 15.7

Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

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