CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2012	Oct. 02, 2011	Sep. 30, 2012	Oct. 02, 2011
Income Statement [Abstract]
Revenues	$ 133,401	$ 138,318	$ 263,562	$ 287,603
Cost of revenues	58,774	64,685	116,422	134,534
Gross profit	74,627	73,633	147,140	153,069
Operating expenses:
Research and development	42,387	39,184	83,931	78,999
Selling, general and administrative	32,750	24,888	69,162	50,817
Total operating expenses	75,137	64,072	153,093	129,816
Operating income (loss)	(510)	9,561	(5,953)	23,253
Interest income (expense) and other, net	(206)	(1,828)	1,794	(1,784)
Income (loss) before income taxes from continuing operations	(716)	7,733	(4,159)	21,469
Income tax expense (benefit)	(33)	(367)	(4,019)	600
Net income (loss) from continuing operations	(683)	8,100	(140)	20,869
Discontinued operations:
Gain from divestiture	886	45,939	886	45,939
Loss from discontinued operations before income taxes	(273)	(7,352)	(5,131)	(14,996)
Expense (benefit) from income taxes	3	(60)	3	(89)
Net income (loss) from discontinued operations	610	38,647	(4,248)	31,032
Net income (loss)	$ (73)	$ 46,747	$ (4,388)	$ 51,901
Basic net income per share - continuing operations (in dollars per share)	$ 0.00	$ 0.06	$ 0.00	$ 0.14
Basic net income (loss) per share - discontinued operations (in dollars per share)	$ 0.00	$ 0.26	$ (0.03)	$ 0.21
Basic net income (loss) per share (in dollars per share)	$ 0.00	$ 0.32	$ (0.03)	$ 0.35
Diluted net income per share - continuing operations (in dollars per share)	$ 0.00	$ 0.06	$ 0.00	$ 0.14
Diluted net income (loss) per share - discontinued operations (in dollars per share)	$ 0.00	$ 0.26	$ (0.03)	$ 0.21
Diluted net income (loss) per share (in dollars per share)	$ 0.00	$ 0.32	$ (0.03)	$ 0.35
Weighted average shares:
Basic (in shares)	143,519	144,682	143,055	146,249
Diluted (in shares)	143,519	146,169	143,055	148,686