Restructuring Restructuring - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Gas Cylinders segment
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 20.1
Elektron segment
Restructuring Cost and Reserve [Line Items]
Asset write down and one time employee benefits	4.6
Gas Cylinders and Elektron Segments
Restructuring Cost and Reserve [Line Items]
Other restructuring costs	$ 1.2

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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