Goodwill Rollforward (Details) $ in Thousands	9 Months Ended
Sep. 29, 2018 USD ($)
Goodwill [Line Items]
Goodwill - Beginning	$ 359,688
Addition due to acquisition	185,136
Foreign currency translation	(2,589)
Goodwill - End	542,235
Specialty Chemicals and Electronic Materials SCEM [Member]
Goodwill [Line Items]
Goodwill - Beginning	304,270
Addition due to acquisition	0
Foreign currency translation	(2,562)
Goodwill - End	301,708
Microcontamination Control [Member]
Goodwill [Line Items]
Goodwill - Beginning	8,007
Addition due to acquisition	175,476
Foreign currency translation	(27)
Goodwill - End	183,456
Advanced Materials Handling AMH [Member]
Goodwill [Line Items]
Goodwill - Beginning	47,411
Addition due to acquisition	9,660
Foreign currency translation	0
Goodwill - End	$ 57,071

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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