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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- Definition

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

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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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 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 - AptoVision Purchase Price Allocation (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2018	Jul. 01, 2017	Jan. 29, 2017
Business Acquisition [Line Items]
Goodwill	$ 341,897		$ 329,703
AptoVision
Business Acquisition [Line Items]
Indefinite-lived intangible asset - IPR&D	2,300
Goodwill	12,194	$ 12,194
Other (liabilities) assets, net	(3,875)
Total consideration	34,619
Developed technology \| AptoVision
Business Acquisition [Line Items]
Finite-lived intangible asset	$ 20,000
Customer relationships \| AptoVision
Business Acquisition [Line Items]
Estimated useful life	3 years
Finite-lived intangible asset	$ 4,000
Minimum \| Developed technology \| AptoVision
Business Acquisition [Line Items]
Estimated useful life	6 years
Maximum \| Developed technology \| AptoVision
Business Acquisition [Line Items]
Estimated useful life	7 years