Goodwill and Intangible Assets, Net - Intangible Assets (Details) - USD ($) $ in Thousands	Jul. 01, 2018	Apr. 01, 2018	Mar. 31, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	$ 564,529	$ 566,330
Impairment		(2,016)
Accumulated Amortization	(393,630)	(383,533)
Net Assets	170,899	180,781
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	338,365	336,402
Impairment		0
Accumulated Amortization	(230,174)	(223,882)
Net Assets	108,191	112,520
Trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	5,391	5,391
Impairment		0
Accumulated Amortization	(5,391)	(5,391)
Net Assets	0	0
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	201,997	201,997
Impairment		0
Accumulated Amortization	(152,458)	(149,416)
Net Assets	49,539	52,581
Intellectual property licenses
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	7,500	7,500
Impairment		0
Accumulated Amortization	(4,201)	(3,901)
Net Assets	3,299	3,599
Software licenses
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	6,237	6,023
Impairment		0
Accumulated Amortization	(1,406)	(943)
Net Assets	4,831	5,080
Total amortizable purchased intangible assets
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	559,490		$ 557,313
Impairment		0
Accumulated Amortization	(393,630)		(383,533)
Net Assets	165,860		$ 173,780
In-process research and development (IPR&D)
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Assets	5,039	9,017
Impairment		(2,016)
Accumulated Amortization	0	0
Net Assets	$ 5,039	$ 7,001