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Accumulated Other Comprehensive Income (Loss) (Details2) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Amortization to net income (loss) of net prior service credits | $ (0.5) | $ (1.8) | $ (3.1)
Amortization of net actuarial loss | 76.7 | 89.5 | 85.3
Settlement gain (loss) | (29.5) | 21.9 | 0.0
Cost of sales | (3,121.8) | (2,466.6) | (2,689.3)
Income (loss) before income taxes | 162.0 | 10.6 | (1,481.9)
Income tax provision | 15.5 | 26.8 | 77.7
Reclassification adjustment included in net income (loss) | 20.0 | 0.0 | 0.0
Revenue from Contract with Customer, Excluding Assessed Tax | (3,836.0) | (2,799.8) | (2,982.1)
Other Postretirement Benefits |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Amortization to net income (loss) of net prior service credits | (0.9) | (2.4) |
Amortization of net actuarial loss | 13.2 | 13.9 |
Settlement gain (loss) | 0.0 | 21.9 |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Post- retirement benefit plans [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Amortization to net income (loss) of net prior service credits | 0.5 | 1.8 | 3.1
Amortization of net actuarial loss | (76.7) | (89.5) | (85.3)
Settlement gain (loss) | (29.5) | 21.9 | 0.0
Income (loss) before income taxes | (105.7) | (65.8) | (82.2)
Income tax provision | (12.0) | (11.9) | (19.7)
Income (loss) | (93.7) | (53.9) | (62.5)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Currency translation adjustment [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Reclassification adjustment included in net income (loss) | (20.0) | 0.0 | 0.0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Derivatives [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Income (loss) before income taxes | 42.8 | 11.4 | (6.0)
Income tax provision | 10.2 | 2.7 | (1.4)
Income (loss) | 32.6 | 8.7 | (4.6)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Derivatives [Member] | Nickel and other raw material contracts [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Cost of sales | 26.9 | 7.1 | (0.8)
Revenue from Contract with Customer, Excluding Assessed Tax | 26.9 | 7.1 | (0.8)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Derivatives [Member] | Natural gas contracts [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Cost of sales | 15.1 | 5.3 | (3.7)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Derivatives [Member] | Foreign Exchange Contract [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Cost of sales | 0.9 | 0.1 | (0.1)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Derivatives [Member] | Interest Rate Swap [Member] |  |  |
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Interest Expense | $ (0.1) | $ (1.1) | $ (1.4)

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