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 consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liability recognized arising from contingent consideration in a business combination.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions - Sualab Co., Ltd. Narrative (Details) - USD ($) $ in Thousands			3 Months Ended				12 Months Ended
	Oct. 16, 2019	Apr. 12, 2017	Dec. 31, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Intangible asset impairment charges			$ 0	$ 0	$ 19,571	$ 0	$ 19,571	$ 0	$ 0
Sualab Co., Ltd. [Member]
Business Acquisition [Line Items]
Tax deductible goodwill	$ 104,609
Purchase price	193,638
Cash paid in purchase price	170,602
Contingent consideration liabilities	$ 24,040
Sualab Co., Ltd. [Member] \| In Process Research and Development [Member]
Business Acquisition [Line Items]
Intangible asset impairment charges					5,900
Sualab Co., Ltd. [Member] \| Maximum [Member] \| In-process Technology [Member]
Business Acquisition [Line Items]
Intangible assets, useful life	6 years
Sualab Co., Ltd. [Member] \| Completed Technology [Member]
Business Acquisition [Line Items]
Intangible assets, useful life	8 years
Sualab Co., Ltd. [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets, useful life	7 years
Sualab Co., Ltd. [Member] \| Trademarks [Member]
Business Acquisition [Line Items]
Intangible assets, useful life	2 years
Sualab Co., Ltd. [Member] \| Non-compete agreements \| Minimum [Member]
Business Acquisition [Line Items]
Intangible assets, useful life		6 years
Sualab Co., Ltd. [Member] \| Non-compete agreements \| Maximum [Member]
Business Acquisition [Line Items]
Intangible assets, useful life	7 years
Sualab Co., Ltd. [Member] \| Completed Technologies [Member]
Business Acquisition [Line Items]
Intangible asset impairment charges					10,070
Sualab Co., Ltd. [Member] \| Customer Contracts And Relationships [Member]
Business Acquisition [Line Items]
Intangible asset impairment charges					$ 3,382