Consolidated Condensed Statements Of Comprehensive Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Consolidated Condensed Statements Of Comprehensive Income [Abstract]
Net sales	$ 190,671	$ 193,774	$ 345,796	$ 292,780
Cost of sales	91,223	93,687	166,850	139,253
Gross profit	99,448	100,087	178,946	153,527
Operating expenses
Research and development	29,722	29,468	58,252	54,378
Selling, general and administrative	19,215	20,194	38,413	38,253
Patent infringement settlements, net	0	0	695	0
Restructuring and other, net	(154)	0	(584)	0
Total operating expenses	48,783	49,662	96,776	92,631
Income from operations	50,665	50,425	82,170	60,896
Interest income, net	201	131	359	258
Other expense, net	(38)	(40)	(55)	(63)
Income before income taxes	50,828	50,516	82,474	61,091
Provision for income taxes	17,461	15,067	28,465	18,715
Net income	33,367	35,449	54,009	42,376
Change in unrealized gain on marketable securities, net of tax	166	17	193	19
Comprehensive income	$ 33,533	$ 35,466	$ 54,202	$ 42,395
Basic earnings per share	$ 0.53	$ 0.55	$ 0.85	$ 0.65
Diluted earnings per share	$ 0.50	$ 0.51	$ 0.82	$ 0.61
Basic weighted average common shares outstanding	63,217	64,924	63,329	64,697
Diluted weighted average common shares outstanding	66,125	69,207	66,203	68,920