Commitments and Contingencies (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Loss Contingencies [Line Items]
Outstanding unconditional contractual commitments for the purchase of raw materials, utilities and equipment	$ 118.4
Outstanding unconditional contractual commitments due to be paid in 2021	$ 41.4
Contingent consideration, payable period	5 years
Contingent consideration, estimated outcome, low	$ 0.0
Contingent consideration, estimated outcome, high	4.3
Insurance Claims
Loss Contingencies [Line Items]
Accrual for insurance obligations	3.0
Amount reimbursable by the insurance company	0.9
Letter of Credit \| Revolving credit facility, due 2024
Loss Contingencies [Line Items]
Letters of credit supporting the reimbursement of workers' compensation and other claims	$ 2.5

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of loss contingency liability.

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

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Contingent Consideration Arrangements, Range Of Outcomes, Payable Period

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