Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net income	$ 2,941,565us-gaap_ProfitLoss	$ 1,862,341us-gaap_ProfitLoss	$ 1,380,033us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	688,150	531,740	365,648
Share-based compensation	155,302us-gaap_ShareBasedCompensation	136,293us-gaap_ShareBasedCompensation	118,566us-gaap_ShareBasedCompensation
Deferred income taxes	(308,222)us-gaap_DeferredIncomeTaxExpenseBenefit	(245,077)us-gaap_DeferredIncomeTaxExpenseBenefit	(116,900)us-gaap_DeferredIncomeTaxExpenseBenefit
Other	(50,320)us-gaap_OtherNoncashIncomeExpense	(27,612)us-gaap_OtherNoncashIncomeExpense	28,822us-gaap_OtherNoncashIncomeExpense
Changes in operating assets and liabilities, net:
Accounts receivable	(512,389)	(126,753)	3,571
Inventory	(185,917)us-gaap_IncreaseDecreaseInInventories	(243,960)us-gaap_IncreaseDecreaseInInventories	(140,309)us-gaap_IncreaseDecreaseInInventories
Other assets	(94,514)	(160,188)	(27,347)
Accrued expenses and other current liabilities	244,378	284,049	273,372
Other liabilities and taxes payable	94,779	318,512	34,112
Other	(30,697)	15,733	(39,671)
Net cash flows provided by operating activities	2,942,115	2,345,078	1,879,897
Cash flows from investing activities:
Proceeds from sales and maturities of marketable securities	2,718,923	5,190,052	2,749,558
Purchases of marketable securities	(3,583,150)	(3,278,091)	(3,334,434)
Acquisition of TYSABRI rights	0	(3,262,719)	0
Contingent consideration related to Fumapharm AG acquisition	(375,000)	(15,000)	0
Acquisitions of businesses	0	0	(72,401)
Purchases of property, plant and equipment	(287,751)	(246,281)	(254,548)
Other	(15,998)	7,371	(38,517)
Net cash flows used in investing activities	(1,542,976)	(1,604,668)	(950,342)
Cash flows from financing activities:
Purchase of treasury stock	(886,779)	(400,309)	(984,715)
Proceeds from issuance of stock for share-based compensation arrangements	54,887	66,770	67,493
Excess tax benefit from share-based compensation	96,376	73,467	54,738
Repayments of borrowings	(2,674)us-gaap_RepaymentsOfDebt	(452,340)us-gaap_RepaymentsOfDebt	(2,428)us-gaap_RepaymentsOfDebt
Other	(17,683)	(4,116)	(12,566)
Net cash flows used in financing activities	(755,873)	(716,528)	(877,478)
Net increase (decrease) in cash and cash equivalents	643,266	23,882	52,077
Effect of exchange rate changes on cash and cash equivalents	(40,904)	7,959	4,102
Cash and cash equivalents, beginning of the year	602,562	570,721	514,542
Cash and cash equivalents, end of the year	$ 1,204,924	$ 602,562	$ 570,721

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.