Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 27, 2019	Dec. 28, 2018
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Total Cost	$ 266,463	$ 258,577
Total Foreign Currency Translation	(16,943)	(15,859)
Finite Life
Accumulated amortization	(87,995)	(76,408)
Total Book Value	161,525	166,310
Trade Names
Indefinite Life
Cost	61,020	59,537
Foreign currency translation	(4,310)	(4,074)
Book value	56,710	55,463
Customer Relationships
Finite Life
Cost	184,410	179,449
Accumulated amortization	(77,345)	(67,322)
Foreign currency translation	(11,581)	(10,817)
Book value	$ 95,484	$ 101,310
Weighted average life in years	13 years	13 years
Patents and Proprietary Technology
Finite Life
Cost	$ 20,013	$ 18,571
Accumulated amortization	(10,053)	(8,647)
Foreign currency translation	(978)	(895)
Book value	$ 8,982	$ 9,029
Weighted average life in years	10 years	10 years
Trademarks, Trade Names and Other
Finite Life
Cost	$ 1,020	$ 1,020
Accumulated amortization	(597)	(439)
Foreign currency translation	(74)	(73)
Book value	$ 349	$ 508
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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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