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

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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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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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Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2021	Jun. 28, 2020	Jul. 04, 2021	Jun. 28, 2020	Dec. 31, 2020	May 26, 2020
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Intangible asset impairment charges	$ 0	$ 19,571	$ 0	$ 19,571
Accumulated amortization	59,973		59,973		$ 58,120
Distribution networks
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Accumulated amortization	38,060		38,060		38,060
Completed technologies
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Accumulated amortization	13,835		13,835		12,397
Completed technologies \| Sualab
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Intangible asset impairment charges		10,070
Customer relationships
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Accumulated amortization	7,520		7,520		7,160
Customer relationships \| EnShape GmbH
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Intangible asset impairment charges		219
Intangible assets acquired		0		$ 0		$ 447
Accumulated amortization						$ 228
Customer relationships \| Sualab
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Intangible asset impairment charges		3,382
Non-compete agreements
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Accumulated amortization	464		464		436
Trademarks
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Accumulated amortization	$ 94		$ 94		$ 67
In-process technologies \| Sualab
Distribution Rights, Developed Technology Rights, Customer Contracts And Relationships, Other Intangible Assets, And Trademarks
Intangible asset impairment charges		$ 5,900