CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 28, 2013	Dec. 29, 2012	Dec. 31, 2011
CONSOLIDATED STATEMENTS OF OPERATIONS
Product sales	$ 502,821	$ 491,654	$ 422,713
Cost of product sales, excluding impairment of intangible assets	163,552	150,037	135,062
Impairment of intangible assets		50,242
Gross profit	339,269	291,375	287,651
Operating expenses:
Selling, general and administrative	144,274	127,984	107,177
Research and development	97,447	87,729	66,314
Total operating expenses	241,721	215,713	173,491
Income from operations	97,548	75,662	114,160
Other income (expense):
Interest expense	(4)	(3)	(4,651)
Interest income and other	2,211	1,658	2,362
Income before taxes	99,755	77,317	111,871
Income tax expense	26,429	21,154	39,296
Net income from continuing operations	73,326	56,163	72,575
Net loss from discontinued operations			(1,031)
Net income	$ 73,326	$ 56,163	$ 71,544
Net income (loss) per common share-Basic:
Continuing operations (in dollars per share)	$ 1.28	$ 0.96	$ 1.23
Discontinued operations (in dollars per share)			$ (0.02)
Net income (in dollars per share)	$ 1.28	$ 0.96	$ 1.21
Net income (loss) per common share-Diluted:
Continuing operations (in dollars per share)	$ 1.26	$ 0.94	$ 1.20
Discontinued operations (in dollars per share)			$ (0.01)
Net income (in dollars per share)	$ 1.26	$ 0.94	$ 1.19
Shares used to compute net income per common share:
Basic (in shares)	57,332	58,563	58,777
Diluted (in shares)	58,324	59,580	62,524