Percentage Of Forecasted Natural Gas Usage Hedged for Year 3

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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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Percentage of Forecasted Natural Gas Usage Hedged for Year 4

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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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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.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Nominal mass used to calculate payments on a derivative instrument.

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Nominal or face amount used to calculate payment on derivative.

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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Derivative Financial Instruments and Hedging (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) lb	Sep. 30, 2020 USD ($)	Sep. 30, 2021 EUR (€)
Derivative Instruments Gain Loss [Line Items]
Percentage of estimated annual nickel requirements			10.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2021			80.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2022			75.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2023			35.00%
Percentage of Forecasted Natural Gas Usage Hedged for 2024			5.00%
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months			$ 8.6
Other Comprehensive Income (Loss) [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	$ 5.2	$ 4.7	10.6	$ (3.1)
Cost of Sales and Interest Expense [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	2.3	(0.3)	$ 4.7	(4.9)
Nickel
Derivative Instruments Gain Loss [Line Items]
Notional amount of nickel hedge (in pounds of nickel) \| lb			4
Interest Rate Swap \| Other Comprehensive Income (Loss) [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	(0.2)	0.1	$ (0.1)	(2.1)
Interest Rate Swap \| Interest Expense [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	(0.2)	(0.2)	(0.6)	(0.7)
Nickel and other raw material contracts \| Other Comprehensive Income (Loss) [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	(0.2)	2.1	2.6	(2.1)
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	1.5	0.7	4.1	(1.3)
Natural gas contracts \| Other Comprehensive Income (Loss) [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	5.6	2.5	8.0	1.2
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	1.0	(0.8)	1.2	(2.8)
Foreign exchange contracts \| Other Comprehensive Income (Loss) [Member] \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	0.0	0.0	0.1	(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	$ 0.0	$ 0.0	$ 0.0	$ (0.1)
Designated as Hedging Instrument \| Foreign exchange forward \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative \| €					€ 0
2024 Term Loan
Derivative Instruments Gain Loss [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.21%		4.21%		4.21%
2024 Term Loan \| Interest Rate Swap
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative	$ 50.0		$ 50.0