Receivables (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowance for trade receivables, beginning balance	$ 22.4	$ 38.6
Additions — charged to expense	3.6	58.0
Transfer from (to) allowance for credit losses	3.4	(17.3)
Net recoveries, write-offs and other	(3.1)	(56.9)
Allowance for trade receivables, ending balance	26.3	22.4
Long term customer receivables	123.1	84.5
Allowance for long term customer receivables [Roll Forward]
Allowance for long term customer receivables, beginning	60.5	47.1
Additions — charged to expense	17.6	13.4
Transfer from (to) allowance for doubtful accounts	(3.4)	17.3
Foreign currency adjustments	(0.5)	(4.1)
Net recoveries, write-offs and other	(13.1)	(13.2)
Allowance for long term customer receivables, ending	$ 61.1	60.5
DuPont Crop restructuring
Allowance for Doubtful Accounts Receivable [Roll Forward]
Write-offs of accounts receivable		$ 42.0