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Derivative Financial Instruments and Hedging (Details2) - Designated as Hedging Instrument - USD ($) $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Asset | $ 7.6 | $ 4.8
Derivative Fair Value Of Derivative Liability | 2.6 | 4.0
Nickel and other raw material contracts | Prepaid expenses and other current assets |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Asset | 3.8 | 3.7
Nickel and other raw material contracts | Other assets |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Asset | 0.8 | 0.7
Nickel and other raw material contracts | Accrued liabilities |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Liability | 0.0 | 0.1
Interest Rate Swap | Accrued liabilities |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Liability | 1.0 | 1.0
Interest Rate Swap | Other long-term liabilities |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Liability | 1.6 | 2.5
Natural gas contracts | Prepaid expenses and other current assets |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Asset | 2.6 | 0.2
Natural gas contracts | Other assets |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Asset | 0.4 | 0.2
Natural gas contracts | Accrued liabilities |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Liability | 0.0 | 0.3
Natural gas contracts | Other long-term liabilities |  |
Derivatives Fair Value [Line Items] |  |
Derivative Fair Value Of Derivative Liability | $ 0.0 | $ 0.1

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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other 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. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4D -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121570589&loc=SL51823488-111719 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624163-113959 + Details
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