CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
Product sales	$ 130,479	$ 118,659	$ 248,204	$ 245,428
Cost of product sales	41,000	36,022	76,073	74,909
Gross profit	89,479	82,637	172,131	170,519
Operating expenses:
Selling, general and administrative	34,924	32,013	69,669	63,214
Research and development	21,506	19,808	46,019	39,504
Total operating expenses	56,430	51,821	115,688	102,718
Income from operations	33,049	30,816	56,443	67,801
Other income and (expense):
Interest expense and other			(4)	(3)
Interest income and other	213	88	1,330	822
Income before income taxes	33,262	30,904	57,769	68,620
Income tax expense	(10,073)	(10,096)	(16,410)	(22,326)
Net income	$ 23,189	$ 20,808	$ 41,359	$ 46,294
Net Income per share:
Basic (in dollars per share)	$ 0.40	$ 0.35	$ 0.72	$ 0.79
Diluted (in dollars per share)	$ 0.40	$ 0.35	$ 0.71	$ 0.78
Shares used to compute income per share:
Basic (in shares)	57,429	58,737	57,457	58,587
Diluted (in shares)	58,120	59,518	58,398	59,513