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Goodwill and Other Intangible Assets - Goodwill (Details) | 12 Months Ended
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Dec. 29, 2024 USD ($) | Dec. 31, 2023 USD ($) | Jan. 01, 2023 USD ($)
Goodwill [Line Items] |  |  |
Goodwill | $ 227,200,000 | $ 227,200,000 |
Accumulated goodwill impairment | $ 528,000,000.0 | 528,000,000.0 | $ 528,000,000.0
Weighted average cost of capital | Fair Value, Inputs, Level 3 [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value measurement input | 0.110 |  |
Long-term growth rate | Fair Value, Inputs, Level 3 [Member] | Minimum |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value measurement input | 0.03 |  |
Long-term growth rate | Fair Value, Inputs, Level 3 [Member] | Maximum |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value measurement input | 0.035 |  |
HPMC |  |  |
Goodwill [Line Items] |  |  |
Goodwill | $ 227,200,000 |  |
Impairment of goodwill | 0 | $ 0 | $ 0
Forged Products |  |  |
Goodwill [Line Items] |  |  |
Goodwill | $ 161,200,000 |  |
Percentage of fair value in excess of carrying value | 95.00% |  |
Specialty Materials [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill | $ 66,000,000.0 |  |

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