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v3.19.3.a.u2

Restructuring Costs (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 USD ($) | Dec. 31, 2019 USD ($) employee | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring charges |  | $ 4.5 | $ 0.0 | $ 0.0
Restructuring and other charges | $ 4.5 | $ 4.5 | $ 0.0 | $ 0.0
Flat Rolled Products |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Restructuring and Related Cost, Expected Number of Positions Eliminated | employee |  | 70 |  |

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- Definition Amount of restructuring charges, remediation cost, and asset impairment loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
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