Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisitions Preliminary Purchase Price Allocation (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 30, 2017	Jul. 01, 2017	Jan. 29, 2017
Business Acquisition [Line Items]
Goodwill	$ 346,575		$ 329,703
AptoVision Technologies Inc. [Member]
Business Acquisition [Line Items]
Indefinite-lived intangible asset	2,300
Goodwill	16,872	$ 16,872
Other (liabilities) assets, net	(8,553)
Total consideration	34,619
Developed Technology [Member] \| AptoVision Technologies Inc. [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset	$ 20,000
Customer Relationships [Member] \| AptoVision Technologies Inc. [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, estimated useful life	3 years
Finite-lived intangible asset	$ 4,000
Minimum [Member] \| Developed Technology [Member] \| AptoVision Technologies Inc. [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, estimated useful life	6 years
Maximum [Member] \| Developed Technology [Member] \| AptoVision Technologies Inc. [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, estimated useful life	7 years