Segment Information - Income by Segment and Reconciliation to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 28, 2018	Oct. 29, 2017	Oct. 28, 2018	Oct. 29, 2017
Segment Reporting Information [Line Items]
Operating income	$ 41,867	$ 17,579	$ 71,706	$ 54,727
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	11,466	15,356	60,947	44,166
Intangible amortization	6,480	7,453	19,921	20,414
Investment impairments, net of offsets	30,000	4,250	30,000	4,250
Changes in the fair value of contingent earn-out obligations	(8,519)	188	(9,419)	188
Interest expense, net	2,355	2,032	6,745	6,107
Non-operating expense, net	(1,182)	(5,517)	(1,914)	(4,681)
Income before taxes and equity in net losses of equity method investments	10,694	16,814	36,875	49,051
Corporate, Non-Segment [Member]
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	11,466	15,356	60,947	44,166
Intangible amortization	6,480	7,453	19,921	20,414
Investment impairments, net of offsets	30,000	4,000	30,000	4,000
Changes in the fair value of contingent earn-out obligations	(8,519)	188	(9,419)	188
Litigation cost net of recoveries	(264)	0	(5,476)	0
Other non-segment related expenses	1,708	2,252	2,981	5,221
Amortization of fair value adjustments related to acquired property, plant and equipment	0	0	0	190
Interest expense, net	2,355	2,032	6,745	6,107
Non-operating expense, net	(1,182)	(5,267)	(1,914)	(4,431)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income	52,738	42,828	140,660	124,906
Semiconductor Products Group [Member]
Segment Reporting Information [Line Items]
Operating income	$ 52,738	$ 42,828	$ 140,660	$ 124,906

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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