Condensed Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Operating activities:
Net income	$ 272.0	$ 504.8
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	38.2	32.6
Amortization of intangible assets	15.9	16.6
Loss on investment, accretion of discounts and amortization of premiums on investments, net	23.8	28.6
Deferred income taxes	(40.2)	(33.8)
Income tax benefits from employee stock plans	7.7	29.7
Excess tax benefit from share-based compensation	(15.2)	(31.1)
Share-based compensation expense	127.8	127.3
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable	42.4	89.7
Inventories	(40.5)	(87.9)
Prepaids and other assets	(69.4)	9.7
Accounts payable	8.2	4.4
Accrued compensation and employee benefits	2.8	(49.1)
Other liabilities	97.4	9.4
Net cash provided by operating activities	470.9	650.9
Investing activities:
Purchase of investments	(1,003.5)	(1,130.0)
Proceeds from sales of investments	623.2	878.1
Proceeds from maturities of investments	553.2	649.8
Purchase of property, plant and equipment, and intellectual property	(40.4)	(75.7)
Acquisition of businesses, net of cash	82.9	0
Net cash provided by investing activities	49.6	322.2
Financing activities:
Proceeds from issuance of common stock	176.0	137.9
Excess tax benefit from share-based compensation	15.2	31.1
Repurchase and retirement of common stock	(1,000.0)	(1,109.2)
Net cash used in financing activities	(808.8)	(940.2)
Effect of exchange rate changes on cash and cash equivalents	(0.8)	0.2
Net decrease in cash and cash equivalents	(289.1)	33.1
Cash and cash equivalents, beginning of period	782.1	553.7
Cash and cash equivalents, end of period	$ 493.0	$ 586.8