Segment Information - Income by Segment and Reconciliation to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 29, 2018	Apr. 30, 2017
Segment Reporting Information [Line Items]
Operating income	$ (3,097)	$ 18,256
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	35,516	13,286
Intangible amortization	6,961	6,286
Interest expense, net	2,190	2,046
Non-operating expense, net	(190)	632
(Loss) income before taxes and equity in net losses of equity method investments	(5,097)	15,578
Corporate, Non-Segment [Member]
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	35,516	13,286
Intangible amortization	6,961	6,286
Other non-segment related expenses	1,432	1,204
Amortization of fair value adjustments related to acquired property, plant and equipment	0	190
Interest expense, net	2,190	2,046
Non-operating expense, net	(190)	632
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income	40,812	39,222
Semiconductor Products Group [Member]
Segment Reporting Information [Line Items]
Operating income	$ 40,812	$ 39,222

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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