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Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 29, 2024 | Oct. 01, 2023 | Sep. 29, 2024 | Oct. 01, 2023
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1,051.2 | $ 1,025.6 | $ 3,189.4 | $ 3,109.7
Percent of revenue | 100.00% | 100.00% | 100.00% | 100.00%
Nickel-based Alloys and Specialty Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 46.00% | 47.00% | 45.00% | 50.00%
Precision and Engineered Strip [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 9.00% | 9.00% | 9.00% | 9.00%
Precision Forgings, Casting and Components [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 20.00% | 18.00% | 19.00% | 17.00%
Titanium and Titanium-based Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 17.00% | 19.00% | 18.00% | 16.00%
Zirconium and Related Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 8.00% | 7.00% | 9.00% | 8.00%
UNITED STATES |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 625.6 | $ 556.8 | $ 1,835.7 | $ 1,713.4
Asia [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 123.3 | 141.2 | 365.0 | 449.2
Europe [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 243.0 | 267.4 | 783.4 | 757.4
CANADA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 31.4 | 23.5 | 84.9 | 76.6
South America, Middle East, and Other [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 27.9 | 36.7 | 120.4 | 113.1
Aerospace and Defense Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 653.8 | 625.8 | 1,953.4 | 1,808.3
Jet Engines- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 365.9 | 329.4 | 1,029.9 | 981.2
Airframes- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 180.8 | 203.6 | 581.7 | 537.7
Defense [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 107.1 | 92.8 | 341.8 | 289.4
Energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 142.5 | 148.9 | 443.8 | 538.6
Conventional energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 72.6 | 87.0 | 241.2 | 325.8
Specialty Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 69.9 | 61.9 | 202.6 | 212.8
Automotive Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 63.8 | 48.1 | 190.6 | 160.3
Electronic Devices Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 49.1 | 44.8 | 142.8 | 115.2
Construction Mining Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 41.8 | 40.0 | 113.2 | 128.8
Food Equipment and Appliances Market |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 12.9 | 16.2 | 41.0 | 58.6
Medical Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 53.1 | 47.5 | 173.9 | 124.4
Other Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 34.2 | 54.3 | 130.7 | 175.5
Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,201.3 | 1,129.9 | 3,582.3 | 3,461.5
Operating Segments | High Performance Materials & Components |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 612.9 | $ 578.1 | $ 1,828.6 | $ 1,670.5
Percent of revenue | 100.00% | 100.00% | 100.00% | 100.00%
Operating Segments | High Performance Materials & Components | Nickel-based Alloys and Specialty Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 43.00% | 42.00% | 41.00% | 45.00%
Operating Segments | High Performance Materials & Components | Precision and Engineered Strip [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 0.00% | 1.00% | 0.00% | 1.00%
Operating Segments | High Performance Materials & Components | Precision Forgings, Casting and Components [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 36.00% | 33.00% | 36.00% | 33.00%
Operating Segments | High Performance Materials & Components | Titanium and Titanium-based Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 21.00% | 24.00% | 23.00% | 21.00%
Operating Segments | High Performance Materials & Components | Zirconium and Related Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 0.00% | 0.00% | 0.00% | 0.00%
Operating Segments | High Performance Materials & Components | UNITED STATES |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 285.8 | $ 242.6 | $ 797.9 | $ 661.1
Operating Segments | High Performance Materials & Components | Asia [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 30.3 | 37.8 | 106.5 | 132.8
Operating Segments | High Performance Materials & Components | Europe [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 201.4 | 217.7 | 636.9 | 619.7
Operating Segments | High Performance Materials & Components | CANADA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 16.4 | 13.1 | 45.4 | 41.7
Operating Segments | High Performance Materials & Components | South America, Middle East, and Other [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 18.5 | 28.3 | 57.6 | 82.4
Operating Segments | High Performance Materials & Components | Aerospace and Defense Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 474.9 | 456.2 | 1,395.0 | 1,287.8
Operating Segments | High Performance Materials & Components | Jet Engines- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 341.9 | 312.5 | 970.6 | 914.2
Operating Segments | High Performance Materials & Components | Airframes- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 84.1 | 104.0 | 263.5 | 242.0
Operating Segments | High Performance Materials & Components | Defense [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 48.9 | 39.7 | 160.9 | 131.6
Operating Segments | High Performance Materials & Components | Energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 28.7 | 22.7 | 75.3 | 83.6
Operating Segments | High Performance Materials & Components | Conventional energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 2.4 | 2.5 | 8.3 | 8.6
Operating Segments | High Performance Materials & Components | Specialty Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 26.3 | 20.2 | 67.0 | 75.0
Operating Segments | High Performance Materials & Components | Automotive Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 4.6 | 7.2 | 13.4 | 19.5
Operating Segments | High Performance Materials & Components | Electronic Devices Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 0.0 | 0.6 | 3.0 | 1.8
Operating Segments | High Performance Materials & Components | Construction Mining Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 4.9 | 7.7 | 19.9 | 26.9
Operating Segments | High Performance Materials & Components | Food Equipment and Appliances Market |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 0.0 | 0.0 | 0.0 | 0.0
Operating Segments | High Performance Materials & Components | Medical Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 28.6 | 28.9 | 97.5 | 70.7
Operating Segments | High Performance Materials & Components | Other Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 10.7 | 16.2 | 40.2 | 47.4
Operating Segments | Advanced Alloys & Solutions |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 588.4 | $ 551.8 | $ 1,753.7 | $ 1,791.0
Percent of revenue | 100.00% | 100.00% | 100.00% | 100.00%
Operating Segments | Advanced Alloys & Solutions | Nickel-based Alloys and Specialty Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 50.00% | 52.00% | 50.00% | 56.00%
Operating Segments | Advanced Alloys & Solutions | Precision and Engineered Strip [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 21.00% | 19.00% | 19.00% | 18.00%
Operating Segments | Advanced Alloys & Solutions | Precision Forgings, Casting and Components [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 0.00% | 0.00% | 0.00% | 0.00%
Operating Segments | Advanced Alloys & Solutions | Titanium and Titanium-based Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 12.00% | 13.00% | 13.00% | 11.00%
Operating Segments | Advanced Alloys & Solutions | Zirconium and Related Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 17.00% | 16.00% | 18.00% | 15.00%
Operating Segments | Advanced Alloys & Solutions | UNITED STATES |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 339.8 | $ 314.2 | $ 1,037.8 | $ 1,052.3
Operating Segments | Advanced Alloys & Solutions | Asia [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 93.0 | 103.4 | 258.5 | 316.4
Operating Segments | Advanced Alloys & Solutions | Europe [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 41.6 | 49.7 | 146.5 | 137.7
Operating Segments | Advanced Alloys & Solutions | CANADA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 15.0 | 10.4 | 39.5 | 34.9
Operating Segments | Advanced Alloys & Solutions | South America, Middle East, and Other [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 9.4 | 8.4 | 62.8 | 30.7
Operating Segments | Advanced Alloys & Solutions | Aerospace and Defense Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 178.9 | 169.6 | 558.4 | 520.5
Operating Segments | Advanced Alloys & Solutions | Jet Engines- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 24.0 | 16.9 | 59.3 | 67.0
Operating Segments | Advanced Alloys & Solutions | Airframes- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 96.7 | 99.6 | 318.2 | 295.7
Operating Segments | Advanced Alloys & Solutions | Defense [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 58.2 | 53.1 | 180.9 | 157.8
Operating Segments | Advanced Alloys & Solutions | Energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 113.8 | 126.2 | 368.5 | 455.0
Operating Segments | Advanced Alloys & Solutions | Conventional energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 70.2 | 84.5 | 232.9 | 317.2
Operating Segments | Advanced Alloys & Solutions | Specialty Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 43.6 | 41.7 | 135.6 | 137.8
Operating Segments | Advanced Alloys & Solutions | Automotive Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 59.2 | 40.9 | 177.2 | 140.8
Operating Segments | Advanced Alloys & Solutions | Electronic Devices Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 49.1 | 44.2 | 139.8 | 113.4
Operating Segments | Advanced Alloys & Solutions | Construction Mining Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 36.9 | 32.3 | 93.3 | 101.9
Operating Segments | Advanced Alloys & Solutions | Food Equipment and Appliances Market |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 12.9 | 16.2 | 41.0 | 58.6
Operating Segments | Advanced Alloys & Solutions | Medical Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 24.5 | 18.6 | 76.4 | 53.7
Operating Segments | Advanced Alloys & Solutions | Other Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 23.5 | 38.1 | 90.5 | 128.1
External Customers | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,051.2 | 1,025.6 | 3,189.4 | 3,109.7
External Customers | Operating Segments | High Performance Materials & Components |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 552.4 | 539.5 | 1,644.3 | 1,537.7
External Customers | Operating Segments | Advanced Alloys & Solutions |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 498.8 | $ 486.1 | $ 1,545.1 | $ 1,572.0

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