Discontinued Operations - Components Comprising Net Income (Loss) from Discontinued Operations, Net (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Loss) income from discontinued operations, net of tax	$ (13.3)	$ 61.4	$ 14.1	$ 108.3
Arysta \| Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	0.0	520.9	65.3	992.5
Cost of sales	0.0	(312.7)	(45.5)	(590.7)
Selling, technical, general and administrative	(0.8)	(135.7)	(37.4)	(271.9)
Research and development	0.0	(14.8)	(4.6)	(26.9)
(Loss) gain on Arysta Sale	(18.8)	0.0	2.5	0.0	$ (448.0)
Operating (loss) profit	(19.6)	57.7	(19.7)	103.0
Other, net	(0.6)	(40.9)	8.7	15.8
(Loss) income from discontinued operations, before income taxes	(20.2)	16.8	(11.0)	118.8
Income tax benefit (expense)	6.9	44.6	25.1	(10.5)
(Loss) income from discontinued operations, net of tax	(13.3)	61.4	14.1	108.3
Net loss (income) from discontinued operations attributable to the non-controlling interests	0.1	(0.4)	0.0	0.2
Net (loss) income from discontinued operations attributable to common stockholders	$ (13.2)	$ 61.0	$ 14.1	$ 108.5

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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