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Accumulated Other Comprehensive Income (Loss) (Details2) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 29, 2024 | Dec. 31, 2023 | Jan. 01, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] |  |  |
Amortization to net income (loss) of net prior service credits | $ (0.5) | $ (0.6) | $ (0.5)
Amortization of net actuarial loss | 5.2 | 6.0 | 13.2
Settlement gain (loss) | 0.0 | (1.1) | (0.7)
Cost of sales | (3,463.9) | (3,371.1) | (3,121.8)
Income (loss) before income taxes | 486.1 | 295.2 | 354.6
Income tax provision (benefit) | 103.4 | (128.2) | 15.5
Reclassification adjustment included in net income | 0.0 | 0.0 | 20.0
Revenue from Contract with Customer, Excluding Assessed Tax | (4,362.1) | (4,173.7) | (3,836.0)
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 | 0.6 | 0.5
Amortization of net actuarial loss | (5.2) | (6.0) | (13.2)
Settlement gain (loss) | 0.0 | (1.1) | (0.7)
Income (loss) before income taxes | (4.7) | (6.5) | (13.4)
Income tax provision (benefit) | (1.1) | (1.4) | (2.8)
Income (loss) | (3.6) | (5.1) | (10.6)
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 | 0.0 | 0.0 | (20.0)
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 | (11.0) | (2.5) | 42.8
Income tax provision (benefit) | (2.6) | (0.6) | 10.2
Income (loss) | (8.4) | (1.9) | 32.6
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 | (4.8) | 3.3 | 26.9
Revenue from Contract with Customer, Excluding Assessed Tax | (4.8) | 3.3 | 26.9
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 | (8.0) | (7.5) | 15.1
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 | 0.2 | 0.3 | 0.9
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 | $ 1.6 | $ 1.4 | $ (0.1)

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