Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Intangible assets subject to amortization (finite-lived)
Gross	$ 1,218.2	$ 1,220.2
Accumulated Amortization	(243.8)	(229.3)
Net	974.4	990.9
Intangible assets not subject to amortization (indefinite-lived)
Indefinite-lived intangible assets	1,637.3	1,638.1
Intangible assets net	2,611.7	2,629.0
Finite and Indefinite lived intangible assets, gross	2,855.5	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	378.2	379.0
Customer relationships
Intangible assets subject to amortization (finite-lived)
Gross	1,137.4	1,139.7
Accumulated Amortization	(198.3)	(184.7)
Net	939.1	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	16.6	16.7
Accumulated Amortization	(6.8)	(6.7)
Net	9.8	10.0
Purchased and licensed technologies
Intangible assets subject to amortization (finite-lived)
Gross	60.2	60.2
Accumulated Amortization	(35.9)	(35.2)
Net	24.3	25.0
Other intangibles
Intangible assets subject to amortization (finite-lived)
Gross	2.3	1.9
Accumulated Amortization	(1.8)	(1.8)
Net	$ 0.5	$ 0.1