Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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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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Unusual Items - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 29, 2019
Unusual or Infrequent Item [Line Items]
Goodwill	$ 161.4	$ 161.4
3D Material Technologies
Unusual or Infrequent Item [Line Items]
Net assets			$ 1.1
Goodwill			$ 0.1