Financial Instruments - Assets and Liabilities Measured at Fair Value (Details) - Recurring - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Asset Category
Total	$ 20.0	$ 10.3
Liability Category
Total	47.3	59.5
Other current assets | Level 2 | Foreign exchange and metals contracts not designated as hedging instruments | Not Designated as Hedging Instrument
Asset Category
Derivative asset	1.2	0.9
Other current assets | Level 2 | Interest rate swaps designated as cash flow hedging instruments | Designated as Hedging Instrument
Asset Category
Derivative asset	0.0	6.5
Other current assets | Level 2 | Cross currency | Designated as Hedging Instrument
Asset Category
Derivative asset	18.5	0.0
Other assets | Level 2 | Designated as Hedging Instrument
Asset Category
Derivative asset	0.0	2.6
Other assets | Level 1
Asset Category
Available for sale equity securities	0.3	0.3
Accrued expenses and other liabilities | Level 2 | Foreign exchange and metals contracts not designated as hedging instruments | Not Designated as Hedging Instrument
Liability Category
Derivatives	0.9	1.2
Accrued expenses and other liabilities | Level 2 | Interest rate swaps designated as cash flow hedging instruments | Designated as Hedging Instrument
Liability Category
Derivatives	1.1	0.6
Other liabilities | Level 2 | Interest rate swaps designated as cash flow hedging instruments | Designated as Hedging Instrument
Liability Category
Derivatives	10.4	0.3
Other liabilities | Level 2 | Cross currency | Designated as Hedging Instrument
Liability Category
Derivatives	15.1	0.0
Other liabilities | Level 3
Liability Category
Long-term contingent consideration	$ 19.8	$ 57.4