Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 27, 2020	Dec. 27, 2019
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Total Cost	$ 269,343	$ 269,663
Total Foreign Currency Translation	(15,527)	(15,100)
Finite Life
Accumulated amortization	(95,747)	(91,940)
Total Book Value	158,069	162,623
Trade Names
Indefinite Life
Cost	61,920	61,920
Foreign currency translation	(3,557)	(3,730)
Book value	58,363	58,190
Customer Relationships
Finite Life
Cost	186,310	186,310
Accumulated amortization	(84,246)	(80,764)
Foreign currency translation	(11,039)	(10,412)
Book value	$ 91,025	$ 95,134
Weighted average life in years	13 years	13 years
Patents and Proprietary Technology
Finite Life
Cost	$ 20,413	$ 20,413
Accumulated amortization	(11,057)	(10,526)
Foreign currency translation	(931)	(885)
Book value	$ 8,425	$ 9,002
Weighted average life in years	10 years	10 years
Trademarks, Trade Names and Other
Finite Life
Cost	$ 700	$ 1,020
Accumulated amortization	(444)	(650)
Foreign currency translation	0	(73)
Book value	$ 256	$ 297
Weighted average life in years	4 years	4 years

Increase (Decrease) Intangible Assets, Translation Adjustments

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of foreign currency translation gain (loss) which increases (decreases) assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a projected indefinite period of benefit.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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