Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Intangible assets subject to amortization (finite-lived)
Gross	$ 1,236.7	$ 1,220.2
Accumulated Amortization	(279.9)	(229.3)
Net	956.8	990.9
Intangible assets not subject to amortization (indefinite-lived)
Indefinite-lived intangible assets	1,653.8	1,638.1
Intangible assets net	2,610.6	2,629.0
Finite and Indefinite lived intangible assets, gross	2,890.5	2,858.3
Crop Protection Brands
Intangible assets not subject to amortization (indefinite-lived)
Indefinite-lived intangible assets	1,259.1	1,259.1
Brands
Intangible assets not subject to amortization (indefinite-lived)
Indefinite-lived intangible assets	394.7	379.0
Customer relationships
Intangible assets subject to amortization (finite-lived)
Gross	1,153.1	1,139.7
Accumulated Amortization	(230.9)	(184.7)
Net	922.2	955.0
Patents
Intangible assets subject to amortization (finite-lived)
Gross	1.7	1.7
Accumulated Amortization	(1.0)	(0.9)
Net	0.7	0.8
Brands
Intangible assets subject to amortization (finite-lived)
Gross	17.5	16.7
Accumulated Amortization	(7.7)	(6.7)
Net	9.8	10.0
Purchased and licensed technologies
Intangible assets subject to amortization (finite-lived)
Gross	61.0	60.2
Accumulated Amortization	(37.3)	(35.2)
Net	23.7	25.0
Other intangibles
Intangible assets subject to amortization (finite-lived)
Gross	3.4	1.9
Accumulated Amortization	(3.0)	(1.8)
Net	$ 0.4	$ 0.1

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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