Consolidated Condensed Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Income Statement [Abstract]
Net sales	$ 388,912	$ 366,305	$ 627,165	$ 620,788
Cost of sales	180,979	181,186	296,738	311,110
Gross profit	207,933	185,119	330,427	309,678
Operating expenses
Research and development	88,239	96,381	177,069	194,313
Selling, general and administrative	33,018	33,160	62,538	65,944
Total operating expenses	121,257	129,541	239,607	260,257
Income from operations	86,676	55,578	90,820	49,421
Interest income	2,530	1,805	5,074	3,511
Interest expense	(280)	(280)	(539)	(539)
Other expense	(568)	(378)	(946)	(168)
Income before income taxes	88,358	56,725	94,409	52,225
Provision (benefit) for income taxes	12,148	(1,448)	13,581	(1,676)
Net income	$ 76,210	$ 58,173	$ 80,828	$ 53,901
Basic earnings per share (in dollars per share)	$ 1.31	$ 0.96	$ 1.39	$ 0.88
Diluted earnings per share (in dollars per share)	$ 1.27	$ 0.93	$ 1.34	$ 0.86
Basic weighted average common shares outstanding (in shares)	58,011	60,472	58,276	60,967
Diluted weighted average common shares outstanding (in shares)	60,213	62,431	60,260	62,810