Condensed Consolidated Statements of Income (USD $) In Millions, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenue:
Product	$ 358.1	$ 295.3	$ 682.6	$ 573.3
Service	67.6	55.4	131.2	106.0
Total revenue	425.7	350.7	813.8	679.3
Cost of revenue:
Product	93.5	72.7	178.3	140.7
Service	25.6	21.2	50.1	41.3
Total cost of revenue	119.1	93.9	228.4	182.0
Gross profit	306.6	256.8	585.4	497.3
Operating expenses:
Selling, general, and administrative	106.5	88.6	205.6	171.4
Research and development	32.0	28.5	63.4	56.5
Total operating expenses	138.5	117.1	269.0	227.9
Income from operations	168.1	139.7	316.4	269.4
Interest and other income, net	4.1	4.5	9.4	8.6
Income before taxes	172.2	144.2	325.8	278.0
Income tax expense	54.8	55.5	104.3	104.0
Net income	$ 117.4	$ 88.7	$ 221.5	$ 174.0
Earnings per share:
Basic	$ 2.99	$ 2.26	$ 5.65	$ 4.45
Diluted	$ 2.91	$ 2.19	$ 5.51	$ 4.31
Shares used in computing earnings per share:
Basic	39.2	39.3	39.2	39.1
Diluted	40.3	40.5	40.2	40.4