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Derivative Financial Instruments and Hedging - Schedule of Derivative Instruments Gain (Loss) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives gain (loss) on hedge transactions | $ 53.8 | $ 15.5 | $ (2.8)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a) | 42.8 | 11.4 | $ (6.0)
Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives gain (loss) on hedge transactions | 41.0 | 11.7 |
Cost of Sales and Interest Expense [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a) | 32.6 | 8.7 |
Nickel and other raw material contracts [Member] | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives gain (loss) on hedge transactions | 27.1 | 6.2 |
Nickel and other raw material contracts [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a) | 20.5 | 5.4 |
Natural gas contracts [Member] | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives gain (loss) on hedge transactions | 10.9 | 5.2 |
Natural gas contracts [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a) | 11.5 | 4.0 |
Foreign Exchange Contract [Member] | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives gain (loss) on hedge transactions | 0.7 | 0.2 |
Foreign Exchange Contract [Member] | Cost of Sales [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a) | 0.7 | 0.1 |
Interest Rate Swap [Member] | Other Comprehensive Income (Loss) [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives gain (loss) on hedge transactions | 2.3 | 0.1 |
Interest Rate Swap [Member] | Interest Expense [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (a) | $ (0.1) | $ (0.8) |

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