Segment Information - Income by Segment and Reconciliation to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 28, 2019	Jul. 29, 2018	Jul. 28, 2019	Jul. 29, 2018
Segment Reporting Information [Line Items]
Operating income (loss)	$ 15,548	$ 32,936	$ 28,365	$ 29,839
Items to reconcile segment operating income to consolidated income before taxes:
Share-based compensation	8,646	13,966	19,974	49,481
Intangible amortization	3,908	6,480	9,051	13,441
Changes in the fair value of contingent earn-out obligations	0	(900)	(2,161)	(900)
Interest expense	2,597	2,200	5,064	4,390
Non-operating expense, net	(1,213)	(542)	(2,256)	(732)
Income before taxes and equity in net gains (losses) of equity method investments	14,164	31,278	25,557	26,181
Corporate, Non-Segment [Member]
Items to reconcile segment operating income to consolidated income before taxes:
Share-based compensation	8,646	13,966	19,974	49,481
Intangible amortization	3,908	6,480	9,051	13,441
Changes in the fair value of contingent earn-out obligations	0	(900)	(2,161)	(900)
Restructuring and other reserves	2,571	85	2,711	431
Litigation cost, net of recoveries	799	(5,857)	725	(5,297)
Transaction and integration related	33	400	1,468	927
Interest expense	2,597	2,200	5,064	4,390
Non-operating expense, net	(1,213)	(542)	(2,256)	(732)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	31,505	47,110	60,133	87,922
Semiconductor Products Group
Segment Reporting Information [Line Items]
Operating income (loss)	$ 31,505	$ 47,110	$ 60,133	$ 87,922

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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