CONSOLIDATED STATEMENTS OF INCOME (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue:
Net product sales	$ 7,563.8us-gaap_SalesRevenueGoodsNet	$ 6,362.3us-gaap_SalesRevenueGoodsNet	$ 5,385.6us-gaap_SalesRevenueGoodsNet
Other revenue	106.6us-gaap_OtherSalesRevenueNet	131.6us-gaap_OtherSalesRevenueNet	121.1us-gaap_OtherSalesRevenueNet
Total revenue	7,670.4us-gaap_Revenues	6,493.9us-gaap_Revenues	5,506.7us-gaap_Revenues
Expenses:
Cost of goods sold (excluding amortization of acquired intangible assets)	385.9us-gaap_CostOfGoodsSold	340.4us-gaap_CostOfGoodsSold	299.1us-gaap_CostOfGoodsSold
Research and development	2,430.6	2,226.2	1,724.2
Selling, general and administrative	2,027.9	1,684.5	1,373.5
Amortization of acquired intangible assets	258.3	262.8	194.5
Acquisition related charges, net	48.7	171.1	169.0
Total costs and expenses	5,151.4us-gaap_CostsAndExpenses	4,685.0us-gaap_CostsAndExpenses	3,760.3us-gaap_CostsAndExpenses
Operating income	2,519.0us-gaap_OperatingIncomeLoss	1,808.9us-gaap_OperatingIncomeLoss	1,746.4us-gaap_OperatingIncomeLoss
Other income and (expense):
Interest and investment income, net	28.2	22.0	15.3
Interest (expense)	(176.1)us-gaap_InterestExpense	(91.6)us-gaap_InterestExpense	(63.2)us-gaap_InterestExpense
Other income (expense), net	(43.7)us-gaap_OtherNonoperatingIncomeExpense	(73.9)us-gaap_OtherNonoperatingIncomeExpense	(17.0)us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	2,327.4	1,665.4	1,681.5
Income tax provision	327.5us-gaap_IncomeTaxExpenseBenefit	215.5us-gaap_IncomeTaxExpenseBenefit	225.3us-gaap_IncomeTaxExpenseBenefit
Net income	$ 1,999.9us-gaap_NetIncomeLoss	$ 1,449.9us-gaap_NetIncomeLoss	$ 1,456.2us-gaap_NetIncomeLoss
Net income per share (Note 1):
Basic (in dollars per share)	$ 2.49us-gaap_EarningsPerShareBasic	$ 1.75us-gaap_EarningsPerShareBasic	$ 1.69us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 2.39us-gaap_EarningsPerShareDiluted	$ 1.68us-gaap_EarningsPerShareDiluted	$ 1.65us-gaap_EarningsPerShareDiluted
Weighted average shares (Note 1):
Basic (in shares)	802.7	827.7	861.9
Diluted (in shares)	836.0	860.6	881.6

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