Debt instrument maturity year.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Face (par) amount of debt instrument at time of issuance.

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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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The number of businesses acquired by the entity during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions - Additional Information (Details) $ in Millions		12 Months Ended
	Jan. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) Business	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Number of businesses acquired \| Business		2
Business acquisition cash paid		$ 64.1
Contingent consideration liability		2.9
Goodwill					$ 107.7
Debt instrument, interest rate					4.70%
Luminati \| 8% convertible secured promissory note
Business Acquisition [Line Items]
Debt instrument, interest rate			8.00%
Face value			$ 10.0
Debt instrument, maturity year			2023
OPM
Business Acquisition [Line Items]
Business combination returned shares value		20.0
Purchase price			$ 15.0
Structil SA and Aerospace and OPM
Business Acquisition [Line Items]
Goodwill		38.0
Recognized intangiable assets and liabilities		$ 32.0
Formax
Business Acquisition [Line Items]
Goodwill	$ 10.2
Purchase price	$ 12.0			$ 22.0
Percentage of ownership interest acquired	50.00%			50.00%
Long-term debt assumed				$ 8.2