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Derivatives, Hedging Programs and Other Financial Instruments, Realized and Unrealized Gains (Losses) Table (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2019 | Mar. 31, 2018
Derivative Instruments Gain Loss [Line Items] |  |
Cost of products sold, excluding depreciation and amortization and other items | $ 315.1 | $ 316.7
Cost of Sales |  |
Derivative Instruments Gain Loss [Line Items] |  |
Cost of products sold, excluding depreciation and amortization and other items |  | 316.7
Cost of Sales | Designated as Hedging Instrument |  |
Derivative Instruments Gain Loss [Line Items] |  |
Loss (gain) recognized in income related to cash flow hedges: | 4.2 | (0.1)
Cost of Sales | Aluminum | Designated as Hedging Instrument |  |
Derivative Instruments Gain Loss [Line Items] |  |
Loss (gain) recognized in income related to cash flow hedges: | 4.2 | 0.3
Cost of Sales | Alloy Metal Hedge | Designated as Hedging Instrument |  |
Derivative Instruments Gain Loss [Line Items] |  |
Loss (gain) recognized in income related to cash flow hedges: | 0.1 | (0.4)
Cost of Sales | Natural Gas | Designated as Hedging Instrument |  |
Derivative Instruments Gain Loss [Line Items] |  |
Loss (gain) recognized in income related to cash flow hedges: | $ (0.1) | $ 0.0

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- Definition The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities. + 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 210.5-03.2(a),(d)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
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