Goodwill Rollforward (Details) $ in Thousands	6 Months Ended
Jun. 29, 2019 USD ($)
Goodwill [Line Items]
Goodwill - Beginning	$ 550,202
Addition due to acquisition	34,516
Goodwill, Purchase Accounting Adjustments	451
Foreign currency translation	(1,841)
Goodwill - End	583,328
Specialty Chemicals and Electronic Materials SCEM
Goodwill [Line Items]
Goodwill - Beginning	301,423
Addition due to acquisition	34,516
Goodwill, Purchase Accounting Adjustments	0
Foreign currency translation	(1,850)
Goodwill - End	334,089
Microcontamination Control
Goodwill [Line Items]
Goodwill - Beginning	191,708
Addition due to acquisition	0
Goodwill, Purchase Accounting Adjustments	451
Foreign currency translation	9
Goodwill - End	192,168
Advanced Materials Handling AMH
Goodwill [Line Items]
Goodwill - Beginning	57,071
Addition due to acquisition	0
Goodwill, Purchase Accounting Adjustments	0
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.

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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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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