Financial Instruments, Risk Management and Fair Value Measurements - Nonrecurring Fair Value (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
FMC Agricultural Solutions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Impairment charge		$ 1.0
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Total Gains (Losses) on Impairment of Crop Protection intangibles		(42.1)
Total Gains (Losses) on Impairment of intangibles	$ (1.8)	(1.3)
Total Gains (Losses) on Total assets	(1.8)	(43.4)
Fair Value, Measurements, Nonrecurring \| Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Impairment of Crop Protection intangibles		1,136.1
Impairment of intangibles	3.1	4.3
Total assets	3.1	1,140.4
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Impairment of Crop Protection intangibles		0.0
Impairment of intangibles	0.0	0.0
Total assets	0.0	0.0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Impairment of Crop Protection intangibles		0.0
Impairment of intangibles	0.0	0.0
Total assets	0.0	0.0
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Impairment of Crop Protection intangibles		1,136.1
Impairment of intangibles	3.1	4.3
Total assets	$ 3.1	$ 1,140.4

Gain (Loss) on Assets Acquired in Business Combination

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Gain (Loss) on Long Lived and Intangible Assets Associated with Exit Activities

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Impairment of Assets Acquired, Fair Value

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Long Lived Assets To Be Abandoned, Fair Value Disclosure

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Restructuring Charges And Asset Disposals

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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