Consolidated Condensed Statements Of Comprehensive Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Dec. 29, 2012	Dec. 31, 2011
Consolidated Condensed Statements Of Comprehensive Income [Abstract]
Net sales	$ 310,133	$ 122,368	$ 602,913	$ 316,212
Cost of sales	152,083	56,338	291,336	148,118
Gross margin	158,050	66,030	311,577	168,094
Operating expenses
Research and development	29,608	23,143	83,986	61,592
Selling, general and administrative	19,021	16,488	57,274	47,854
Restructuring and other costs, net	3,539	0	3,539	0
Gain on sale of asset	(247)	0	(247)	0
Total operating expenses	51,921	39,631	144,552	109,446
Income from operations	106,129	26,399	167,025	58,648
Interest income, net	76	112	334	378
Other expense, net	(31)	(71)	(94)	(115)
Income before income taxes	106,174	26,440	167,265	58,911
Provision for income taxes	38,312	9,709	57,027	21,755
Net income	67,862	16,731	110,238	37,156
Change in unrealized gain (loss) on marketable securities	(30)	63	(11)	(69)
Comprehensive income	$ 67,832	$ 16,794	$ 110,227	$ 37,087
Basic earnings per share	$ 1.04	$ 0.26	$ 1.70	$ 0.57
Diluted earnings per share	$ 0.99	$ 0.25	$ 1.60	$ 0.55
Basic weighted average common shares outstanding	65,055	63,957	64,859	65,161
Diluted weighted average common shares outstanding	68,866	66,989	68,946	68,099