Derivative, Notional Amount, Contracts Entered During Period

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- Definition

Derivative, Notional Amount, Net Settled

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No definition available.

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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments

+ References

No definition available.

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- Definition

Percentage Of Forecasted Natural Gas Usage Hedged for Year 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

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No definition available.

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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

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No definition available.

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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.

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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

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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

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- Definition

The amount of cash received during the period on settlement of a hedge.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- References

No definition available.

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- Definition

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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No definition available.

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- Definition

Nominal mass used to calculate payments on a derivative instrument.

+ References

No definition available.

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- Definition

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

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

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

+ References

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Derivative Financial Instruments and Hedging - Narrative (Details) € in Millions, lb in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) lb	Dec. 31, 2016 USD ($)	Dec. 31, 2015 EUR (€)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 EUR (€)	Dec. 31, 2016 EUR (€)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Maximum amount of time hedged for nickel requirements	2021
Percentage of estimated annual nickel requirements	20.00%
Derivative [Line Items]
Pre-tax cash flow hedge gain (loss) to be reclassified within twelve months	$ (7.6)
Nickel [Member]
Derivative [Line Items]
Derivative notional amount (in pounds of nickel) \| lb	18
Cash Flow Hedging [Member] \| Natural gas contracts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Percentage of forecasted natural gas usage hedged for 2019	35.00%
Percentage of forecasted natural gas usage hedged for 2020	15.00%
Pre-tax loss on ineffective portion of hedge		$ 1.3		$ 3.3
Percentage Of Forecasted Natural Gas Usage Hedged for 2018	40.00%
Cash Flow Hedging [Member] \| Foreign Exchange Forward [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative notional amount settled \| €			€ 211.9
Proceeds from hedge				56.5
Pre-tax gain on ineffective portion of hedge				14.3
Fair Value Hedging [Member] \| Foreign Exchange Forward [Member] \| Designated as Hedging Instrument [Member] \| Maturity Dates Through 2017 [Member]
Derivative [Line Items]
Derivative notional amount \| €			139.2		€ 0.0	€ 43.2
Notional amount of derivatives entered during period \| €			€ 244.7
Cost of Sales [Member] \| Fair Value Hedging [Member] \| Foreign Exchange Forward [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Gain (loss) on derivatives	$ (2.7)	$ 1.0		$ 9.0