Segment Information - Income by Segment and Reconciliation to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 27, 2019	Oct. 28, 2018	Oct. 27, 2019	Oct. 28, 2018
Segment Reporting Information [Line Items]
Operating income (loss)	$ 22,165	$ 41,867	$ 50,530	$ 71,706
Items to reconcile segment operating income to consolidated income before taxes:
Share-based compensation	8,767	11,466	28,741	60,947
Intangible amortization	3,770	6,480	12,821	19,921
Investment impairments	0	30,000	0	30,000
Changes in the fair value of contingent earn-out obligations	(152)	(8,519)	(2,313)	(9,419)
Interest expense	2,183	2,355	7,247	6,745
Non-operating income, net	(644)	(1,182)	(2,900)	(1,914)
Income before taxes and equity in net gains (losses) of equity method investments	20,626	10,694	46,183	36,875
Corporate, Non-Segment
Items to reconcile segment operating income to consolidated income before taxes:
Share-based compensation	8,767	11,466	28,741	60,947
Intangible amortization	3,770	6,480	12,821	19,921
Investment impairments	0	30,000	0	30,000
Changes in the fair value of contingent earn-out obligations	(152)	(8,519)	(2,313)	(9,419)
Restructuring and other reserves	0	86	2,711	518
Litigation cost, net of recoveries	205	(264)	930	(5,562)
Transaction and integration related	(851)	1,622	617	2,549
Interest expense	2,183	2,355	7,247	6,745
Non-operating income, net	(644)	(1,182)	(2,900)	(1,914)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	33,904	52,738	94,037	140,660
Semiconductor Products Group
Segment Reporting Information [Line Items]
Operating income (loss)	$ 33,904	$ 52,738	$ 94,037	$ 140,660

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

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