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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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, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) lb	Sep. 30, 2022 USD ($)	Sep. 30, 2023 EUR (€)	Sep. 30, 2023 USD ($)
Derivative Instruments Gain Loss [Line Items]
Percentage of estimated annual nickel requirements			9.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2023			80.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2024			55.00%
Percentage Of Forecasted Natural Gas Usage Hedged for 2025			15.00%
Reclassification of Cash Flow Hedge Gain (Loss) [Abstract]
Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months			$ (4.3)
Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	$ (1.4)	$ 5.4	(0.1)	$ 24.7
Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	(2.4)	5.8	$ (15.7)	36.8
Nickel
Derivative Instruments Gain Loss [Line Items]
Notional amount of nickel hedge (in pounds of nickel) \| lb			6
Interest Rate Swap \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	0.3	0.0	$ 0.8	(0.3)
Interest Rate Swap \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	0.1	0.6	0.3	2.1
Nickel and other raw material contracts \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	(0.4)	0.8	3.5	15.3
Nickel and other raw material contracts \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	(1.6)	(0.7)	(8.5)	16.6
Natural gas contracts \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	(1.4)	4.1	(4.6)	9.1
Natural gas contracts \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	(1.0)	5.4	(7.8)	17.2
Foreign exchange contracts \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain Loss Reclassified From Accumulated OCI Into Income Effective Portion Net	0.1	0.5	0.2	0.6
Foreign exchange contracts \| Cash Flow Hedging \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Net derivative gain (loss) on hedge transactions	$ 0.1	$ 0.5	$ 0.3	$ 0.9
Designated as Hedging Instrument \| Foreign exchange forward \| Cash Flow Hedging
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative \| €					€ 0
2027 Term Loan
Derivative Instruments Gain Loss [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					4.21%	4.21%
2027 Term Loan \| Interest Rate Swap
Derivative Instruments Gain Loss [Line Items]
Notional amount of derivative						$ 50.0