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Derivative Financial Instruments and Hedging (Details) € in Millions, lb in Millions, $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) lb | Mar. 31, 2017 USD ($) | Mar. 31, 2018 EUR (€)
Derivative Instruments Gain Loss [Line Items] |  |  |
Percentage of estimated annual nickel requirements | 15.00% |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2018 | 35.00% |  |
Percentage Of Forecasted Natural Gas Usage Hedged for 2019 | 35.00% |  |
Percentage of Forecasted Natural Gas Usage Hedged for 2020 | 15.00% |  |
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract] |  |  |
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months | $ 8.1 |  |
Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Recognized In Other Comprehensive Income Effective Portion Net | 2.5 | $ (1.5) |
Cost Of Sales | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | $ 2.3 | 0.6 |
Nickel |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Notional amount of nickel hedge (in pounds of nickel) | lb | 15 |  |
Nickel and other raw material contracts | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Recognized In Other Comprehensive Income Effective Portion Net | $ 3.1 | 0.2 |
Nickel and other raw material contracts | Cost Of Sales | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | 2.8 | (0.6) |
Natural gas contracts | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Recognized In Other Comprehensive Income Effective Portion Net | 0.2 | (1.6) |
Natural gas contracts | Cost Of Sales | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (0.3) | (1.4) |
Foreign exchange contracts | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Recognized In Other Comprehensive Income Effective Portion Net | (0.8) | (0.1) |
Foreign exchange contracts | Cost Of Sales | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net | (0.2) | 2.6 |
Designated as Hedging Instrument | Foreign exchange forward | Maturity Dates Through 2018 [Member] | Cash Flow Hedging |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Notional amount of derivative | € |  |  | € 21
Not Designated as Hedging Instrument | Foreign exchange forward | Maturity Dates Through 2018 [Member] |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Notional amount of derivative | € |  |  | € 10
Not Designated as Hedging Instrument | Foreign exchange contracts | Cost Of Sales |  |  |
Derivative Instruments Gain Loss [Line Items] |  |  |
Derivative Instruments Gain Loss Recognized In Income Net | $ (0.2) | $ (0.1) |

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- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage + References No definition available. + Details
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- Definition Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of annual estimated usage in production + References No definition available. + Details
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- Definition Percentage of forecasted natural usage hedged year 3 + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + Details
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