CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Income Statement [Abstract]
Revenues	$ 169,498	$ 137,093	$ 330,405	$ 263,395
Cost of revenues	62,952	55,217	124,625	107,510
Gross profit	106,546	81,876	205,780	155,885
Operating expenses:
Research and development	35,301	30,742	69,055	62,792
Selling, general and administrative	29,227	26,795	57,370	52,254
Total operating expenses	64,528	57,537	126,425	115,046
Operating income	42,018	24,339	79,355	40,839
Interest income and other, net	1,016	405	2,834	1,267
Income before income taxes from continuing operations	43,034	24,744	82,189	42,106
Income tax provision	611	498	1,046	749
Net income from continuing operations	42,423	24,246	81,143	41,357
Discontinued operations:
Gain from divestiture before income taxes	0	0	0	16,840
Loss from discontinued operations before income taxes	0	(9,747)	(547)	(21,900)
Income tax provision	0	57	15	12
Net loss from discontinued operations	0	(9,804)	(562)	(5,072)
Net income	$ 42,423	$ 14,442	$ 80,581	$ 36,285
Basic net income per share - continuing operations (in dollars per share)	$ 0.29	$ 0.16	$ 0.55	$ 0.28
Basic net income (loss) per share - discontinued operations (in dollars per share)	0.00	(0.06)	0.00	(0.04)
Basic net income (loss) per share (in dollars per share)	0.29	0.10	0.55	0.24
Diluted net income per share - continuing operations (in dollars per share)	0.28	0.16	0.53	0.27
Diluted net income (loss) per share - discontinued operations (in dollars per share)	0.00	(0.07)	0.00	(0.03)
Diluted net income (loss) per share (in dollars per share)	$ 0.28	$ 0.09	$ 0.53	$ 0.24
Weighted average shares:
Basic (shares)	147,724	148,683	148,058	148,983
Diluted (shares)	152,152	153,784	152,997	153,816