Exit activities - Restructuring and Related Costs (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Total	$ 17.6
Special Charges
Restructuring Cost and Reserve [Line Items]
Inventory and asset write-offs	8.5
Special Charges \| One-time Termination Benefits
Restructuring Cost and Reserve [Line Items]
Severance costs and other	4.5
Cost of Sales \| Facility Closing
Restructuring Cost and Reserve [Line Items]
Accelerated depreciation	$ 4.6

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

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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