Fair Value Measurement (Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Change in the Fair Value of Contigent Consideration Receivable
Balance at beginning of period	$ 38.3	$ 37.8
Gain/(loss) recognized in the income statement (within Gain/(loss) on sale of product rights) due to change in fair value during the period	5.4	7.2
Reclassification of amounts due to Other receivables within Other current assets	(5.0)	(5.6)
Amounts recorded to other comprehensive income (within foreign currency translation adjustments)	(1.0)	0.8
Balance at end of period	37.7	40.2
Change in the Fair Value of Contigent Consideration Payable
Balance at beginning of period	136.4	0
Initial recognition of contingent consideration payable	233.8	0
Loss recognized in the income statement (within Integration and acquisition costs) due to change in fair value during the period	1.8	0
Reclassification of amounts to Other current liabilities	(5.8)	0
Balance at end of period	$ 366.2	$ 0