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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, 2019 USD ($) class	Dec. 31, 2018 USD ($)	Dec. 31, 2017 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	$ 26.3	$ 22.4	$ 38.6
Allowance for long term customer receivables, beginning		61.1	61.1	60.5	47.1
Additions — charged to expense			$ 21.2	71.4	22.1
Investments
Maximum ownership percentage for equity method investments			50.00%
Capitalized Interest
Capitalized interest costs			$ 4.7	4.1	1.6
Asset Retirement Obligation [Abstract]
Asset retirement obligation		35.7	35.7	2.6
Goodwill and Intangible Assets
Impairment loss on indefinite-lived intangible asset					42.1
Environmental obligations
Charges to expense for new losses			138.8	$ 178.2	$ 105.6
Pocatello
Environmental obligations
Charges to expense for new losses	$ 72.8	$ 72.8	$ 72.8
Minimum
Goodwill and Intangible Assets
Weighted avg. useful life at December 31, 2019			3 years
Maximum
Goodwill and Intangible Assets
Weighted avg. useful life at December 31, 2019			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			20 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%