Accumulated Other Comprehensive Income (Loss) (Reclassification of AOCI) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Other Comprehensive Income (Loss)
Net product sales	$ 2,494.7	$ 2,055.2
Interest (expense)	(121.9)	(49.2)
Income tax benefit (expense)	(120.9)	(108.2)
Interest and investment income, net	6.8	9.0
Gains (Losses) Reclassified Out of Accumulated Other Comprehensive Income
Other Comprehensive Income (Loss)
Net income	80.6	70.1
Gains (Losses) Reclassified Out of Accumulated Other Comprehensive Income | Gains (losses) from cash-flow hedges: | Foreign exchange contracts
Other Comprehensive Income (Loss)
Net product sales	88.4	70.5
Gains (Losses) Reclassified Out of Accumulated Other Comprehensive Income | Gains (losses) from cash-flow hedges: | Treasury rate lock agreements
Other Comprehensive Income (Loss)
Interest (expense)	(1.3)	(0.9)
Gains (Losses) Reclassified Out of Accumulated Other Comprehensive Income | Gains (losses) from cash-flow hedges: | Interest rate swap agreements
Other Comprehensive Income (Loss)
Interest (expense)	(0.4)	(0.4)
Income tax benefit (expense)	0.7	0.5
Gains (Losses) Reclassified Out of Accumulated Other Comprehensive Income | Gains (losses) from available-for-sale marketable securities:
Other Comprehensive Income (Loss)
Income tax benefit (expense)	3.6	(0.2)
Interest and investment income, net	$ (10.4)	$ 0.6