Condensed Consolidated Income Statements (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Revenue:
Product and maintenance	$ 341,601	$ 310,118	$ 1,007,855	$ 893,916
Service	25,046	28,415	75,539	86,923
Total revenue	366,647	338,533	1,083,394	980,839
Costs and Expenses:
Cost of product and maintenance	32,546	34,461	90,488	94,079
Cost of service	17,190	16,809	50,682	53,254
Marketing and sales	98,094	82,461	283,773	246,674
Research and development	138,078	115,078	398,557	335,703
General and administrative	27,582	26,350	91,833	84,364
Amortization of acquired intangibles	5,141	3,876	14,259	11,305
Restructuring and other charges	86	57	2,594	49
Total costs and expenses	318,717	279,092	932,186	825,428
Income from operations	47,930	59,441	151,208	155,411
Interest expense	(9,583)	(8,737)	(28,373)	(25,840)
Other income (expense), net	2,535	(131)	6,728	5,972
Income before provision (benefit) for income taxes	40,882	50,573	129,563	135,543
Provision (benefit) for income taxes	2,382	(8,011)	3,025	9,469
Net income	$ 38,500	$ 58,584	$ 126,538	$ 126,074
Net income per share - basic (in usd per share)	$ 0.14	$ 0.22	$ 0.46	$ 0.47
Net income per share - diluted (in usd per share)	$ 0.13	$ 0.21	$ 0.43	$ 0.45
Weighted average common shares outstanding - basic (in shares)	278,977	271,350	277,034	269,643
Weighted average common shares outstanding - diluted (in shares)	296,958	283,328	294,531	278,760