CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 29, 2015	Mar. 30, 2014	Mar. 31, 2013
Income Statement [Abstract]
Revenues	$ 572,905	$ 484,779	$ 484,452
Cost of revenues	227,601	211,877	214,728
Gross profit	345,304	272,902	269,724
Operating expenses:
Research and development	127,688	140,799	159,471
Selling, general and administrative	106,469	101,148	117,648
Total operating expenses	234,157	241,947	277,119
Operating income (loss)	111,147	30,955	(7,395)
Gain on divestitures, net	0	78,632	7,986
Other-than-temporary impairment loss on investments	0	0	(1,708)
Interest income and other, net	4,791	2,707	1,708
Income before income taxes from continuing operations	115,938	112,294	591
Income tax expense (benefit)	1,357	981	(2,120)
Net income from continuing operations	114,581	111,313	2,711
Discontinued operations:
Gain from divestiture	16,840	0	886
Loss from discontinued operations before income taxes	(37,237)	(22,938)	(23,653)
Income tax expense	275	11	116
Net loss from discontinued operations	(20,672)	(22,949)	(22,883)
Net income (loss)	$ 93,909	$ 88,364	$ (20,172)
Basic net income per share - continuing operations (in dollars per share)	$ 0.77	$ 0.74	$ 0.02
Basic net loss per share - discontinued operations (in dollars per share)	$ (0.14)	$ (0.15)	$ (0.16)
Basic net income (loss) per share (in dollars per share)	$ 0.63	$ 0.59	$ (0.14)
Diluted net income per share - continuing operations (in dollars per share)	$ 0.74	$ 0.73	$ 0.02
Diluted net loss per share - discontinued operations (in dollars per share)	$ (0.13)	$ (0.15)	$ (0.16)
Diluted net income (loss) per share (in dollars per share)	$ 0.61	$ 0.58	$ (0.14)
Weighted average shares:
Basic (shares)	148,714	149,480	144,014
Diluted (shares)	153,983	153,369	145,678