Supplemental Information - Other Assets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Other assets
Argentina government receivable	$ 55.9	$ 55.0
Advance to contract manufacturers	15.9	15.9
Capitalized software, net	2.1	1.1
Prepayment associated with long-term supply agreement	10.0	10.0
Tax related items	4.8	3.6
Other assets	8.6	5.9
Total	97.3	91.5
Condensed Balance Sheet Statements, Captions [Line Items]
Deferred asset	3.3
Nikolov V. Livent Corp \| Pending Litigation
Condensed Balance Sheet Statements, Captions [Line Items]
Insurance reimbursement receivable	4.9
Argentina Government
Condensed Balance Sheet Statements, Captions [Line Items]
Export tax and export rebate receivable	$ 40.4	$ 38.0

Deferred Tax Asset on Uncertain Tax Positions (UTPs)

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- Definition

Export Tax And Export Rebate Receivable

+ References

No definition available.

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- Definition

Receivable From Government Entities, Noncurrent

+ References

No definition available.

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- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
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- Definition

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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- Definition

Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

+ References

No definition available.

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Amount of noncurrent assets classified as other.

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Sum of the carrying amounts as of the balance sheet date of amounts paid in advance for expenses which will be charged against earnings in periods after one year or beyond the operating cycle, if longer.

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- Definition

The carrying amount as of the balance sheet date of capitalized preproduction costs incurred on long-term supply arrangements, including recoverable costs to design and develop products.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (a)
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