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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Principal Accounting Policies and Related Financial Information (Details) shares in Millions, $ in Millions		3 Months Ended	12 Months Ended
	Nov. 15, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) class	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Oct. 15, 2018 shares
Nature of Operations
Number of major classes of crop protection \| class			3
Trade receivable, net of allowance
Allowance for trade receivable		$ 26.3	$ 27.9	$ 26.3	$ 22.4
Allowance for long-term receivables		61.1	24.7	61.1	60.5
Additions — charged to expense			$ 4.7	21.2	71.4
Investments
Maximum ownership percentage for equity method investments			50.00%
Capitalized Interest
Capitalized interest costs			$ 3.5	4.7	4.1
Asset Retirement Obligation [Abstract]
Asset retirement obligation		35.7	30.7	35.7
Environmental obligations
Charges to expense for new losses			53.2	$ 138.8	$ 178.2
Pocatello
Environmental obligations
Charges to expense for new losses	$ 72.8	$ 72.8	$ 82.6
Minimum
Goodwill and Intangible Assets
Weighted avg. useful life remaining at December 31, 2020			3 years
Maximum
Goodwill and Intangible Assets
Weighted avg. useful life remaining at December 31, 2020			20 years
Land Improvements
Property, plant and equipment and capitalized software
Useful lives			20 years
Building \| Minimum
Property, plant and equipment and capitalized software
Useful lives			15 years
Building \| Maximum
Property, plant and equipment and capitalized software
Useful lives			40 years
Machinery and Equipment \| Minimum
Property, plant and equipment and capitalized software
Useful lives			3 years
Machinery and Equipment \| Maximum
Property, plant and equipment and capitalized software
Useful lives			18 years
Software Development \| Minimum
Property, plant and equipment and capitalized software
Useful lives			3 years
Software Development \| Maximum
Property, plant and equipment and capitalized software
Useful lives			10 years
Livent
Nature of Operations
Shares owned by parent (in shares) \| shares						123
Outstanding shares of parent, percentage						84.00%