Segment Information - Income by Segment and Reconciliation to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 29, 2018	Jul. 30, 2017	Jul. 29, 2018	Jul. 30, 2017
Segment Reporting Information [Line Items]
Operating income	$ 32,936	$ 18,892	$ 29,839	$ 37,148
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	13,966	15,525	49,481	28,810
Intangible amortization	6,480	6,675	13,441	12,961
Changes in the fair value of contingent earn-out obligations	(900)	0	(900)	0
Interest expense, net	2,200	2,029	4,390	4,075
Non-operating expense, net	(542)	204	(732)	836
Income before taxes and equity in net losses of equity method investments	31,278	16,659	26,181	32,237
Corporate, Non-Segment [Member]
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	13,966	15,525	49,481	28,810
Intangible amortization	6,480	6,675	13,441	12,961
Changes in the fair value of contingent earn-out obligations	(900)	0	(900)	0
Litigation cost net of recoveries	(6,632)	0	(6,632)	0
Other non-segment related expenses	1,260	1,764	2,693	2,969
Amortization of fair value adjustments related to acquired property, plant and equipment	0	0	0	190
Interest expense, net	2,200	2,029	4,390	4,075
Non-operating expense, net	(542)	204	(732)	836
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income	47,110	42,856	87,922	82,078
Semiconductor Products Group [Member]
Segment Reporting Information [Line Items]
Operating income	$ 47,110	$ 42,856	$ 87,922	$ 82,078

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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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