Percentage Of Forecasted Natural Gas Usage Hedged for Year 1

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Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of estimated annual domestic (U.S.) usage

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No definition available.

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Aggregate notional amount of price risk derivatives for instruments with notional amounts expressed in percentage of annual estimated usage in production

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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

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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

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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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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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Nominal mass used to calculate payments on a derivative instrument.

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The loss recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Derivative Financial Instruments and Hedging (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($) lb	Mar. 31, 2016 USD ($)	Mar. 31, 2017 EUR (€)
Derivative Instruments Gain Loss [Line Items]
Percentage of estimated annual nickel requirements	35.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2017	75.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2018	25.00%
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months	$ (2.5)
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	(1.5)	$ (5.7)
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	0.6	(2.4)
Selling And Administrative Expenses \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Recognized In Income Ineffective Portion And Amount Excluded From Effectiveness Testing Net	$ 0.0	(0.7)
Nickel
Derivative Instruments Gain Loss [Line Items]
Notional amount of nickel hedge (in pounds of nickel) \| lb	28
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	$ 0.2	(3.4)
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	(0.6)	(3.9)
Nickel and other raw material contracts \| Selling And Administrative Expenses \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Recognized In Income Ineffective Portion And Amount Excluded From Effectiveness Testing Net	0.0	0.0
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	(1.6)	(2.0)
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	(1.4)	(3.2)
Natural gas contracts \| Selling And Administrative Expenses \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Recognized In Income Ineffective Portion And Amount Excluded From Effectiveness Testing Net	0.0	(0.7)
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	(0.1)	(0.3)
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	2.6	4.7
Foreign exchange contracts \| Selling And Administrative Expenses \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Recognized In Income Ineffective Portion And Amount Excluded From Effectiveness Testing Net	0.0	0.0
Designated as Hedging Instrument \| Foreign exchange forward \| Cost Of Sales \| Fair Value Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Recognized In Income Net	(0.3)	(5.6)
Designated as Hedging Instrument \| Foreign exchange forward \| Maturity Dates Through 2017 [Member] \| Fair Value Hedging
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative \| €			€ 32.4
Designated as Hedging Instrument \| Natural gas contracts \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Loss on Cash Flow Hedge Ineffectiveness		1.1
Not Designated as Hedging Instrument \| Foreign exchange forward \| Maturity Dates Through 2017 [Member]
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative \| €			€ 10.0
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	$ (0.1)	$ (0.6)