Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Intangible assets subject to amortization (finite-lived)
Gross	$ 1,223.3	$ 1,220.2
Accumulated Amortization	(260.4)	(229.3)
Net	962.9	990.9
Intangible assets not subject to amortization (indefinite-lived)
Indefinite-lived intangible assets	1,641.0	1,638.1
Intangible assets net	2,603.9	2,629.0
Finite and Indefinite lived intangible assets, gross	2,864.3	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	381.9	379.0
Customer relationships
Intangible assets subject to amortization (finite-lived)
Gross	1,141.3	1,139.7
Accumulated Amortization	(212.9)	(184.7)
Net	928.4	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	16.8	16.7
Accumulated Amortization	(7.7)	(6.7)
Net	9.1	10.0
Purchased and licensed technologies
Intangible assets subject to amortization (finite-lived)
Gross	60.4	60.2
Accumulated Amortization	(36.2)	(35.2)
Net	24.2	25.0
Other intangibles
Intangible assets subject to amortization (finite-lived)
Gross	3.1	1.9
Accumulated Amortization	(2.6)	(1.8)
Net	$ 0.5	$ 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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