Supplemental Information - Accrued and Other Current Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Accrued and other current liabilities
Plant restructuring reserves	$ 3.2	$ 3.3
Retirement liability - 401K	1.9	2.7
Accrued payroll	9.9	6.7
Derivative liabilities	0.2	0.0
Severance related	1.7	0.0
Environmental reserves, current	0.7	0.5
Other accrued and other current liabilities	16.2	23.2
Total	$ 33.8	$ 36.4

Accrued Severance Costs

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement that is payable within one year of the balance sheet date.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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