Segment Information - Income by Segment and Reconciliation to Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 29, 2017	Oct. 30, 2016	Oct. 29, 2017	Oct. 30, 2016
Segment Reporting Information [Line Items]
Operating income	$ 17,579	$ 39,099	$ 54,727	$ 68,794
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	15,356	9,395	44,166	21,198
Intangible amortization	7,453	6,286	20,414	19,017
Changes in the fair value of contingent earn-out obligations	188	0	188	(162)
Interest expense, net	2,032	1,890	6,107	5,857
Non-operating expense, net	(1,267)	690	(431)	871
Income before taxes and equity in net losses of equity method investments	16,814	36,519	49,051	62,066
Corporate, Non-Segment [Member]
Items to reconcile segment operating income to consolidated income before taxes
Share-based compensation	15,356	9,395	44,166	21,198
Intangible amortization	7,453	6,286	20,414	19,017
Changes in the fair value of contingent earn-out obligations	188	0	188	(162)
Other non-segment related expenses	2,252	3,139	5,221	5,939
Amortization of fair value adjustments related to acquired property, plant and equipment	0	308	190	925
Interest expense, net	2,032	1,890	6,107	5,857
Non-operating expense, net	(1,267)	690	(431)	871
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income	42,828	58,227	124,906	115,711
Semiconductor Products Group [Member]
Segment Reporting Information [Line Items]
Operating income	42,828	33,013	124,906	92,973
All others [Member]
Segment Reporting Information [Line Items]
Operating income	$ 0	$ 25,214	$ 0	$ 22,738

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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 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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The net amount of nonoperating interest income (expense).

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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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