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Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 1,046.0 | $ 959.5 | $ 2,084.1 | $ 1,793.6
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 | 52.00% | 52.00% | 52.00% | 51.00%
Precision and Engineered Strip [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 9.00% | 14.00% | 10.00% | 15.00%
Precision Forgings, Casting and Components [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 17.00% | 15.00% | 16.00% | 15.00%
Titanium and Titanium-based Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 14.00% | 11.00% | 14.00% | 10.00%
Zirconium and Related Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 8.00% | 8.00% | 8.00% | 9.00%
UNITED STATES |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 568.3 | $ 568.6 | $ 1,156.6 | $ 1,046.3
Asia [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 154.5 | 154.9 | 308.0 | 314.2
Europe [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 251.4 | 183.8 | 490.0 | 343.7
CANADA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 29.9 | 24.4 | 53.1 | 43.4
South America, Middle East, and Other [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 41.9 | 27.8 | 76.4 | 46.0
Aerospace and Defense Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 606.8 | 436.4 | 1,182.5 | 803.2
Jet Engines- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 340.9 | 248.7 | 651.8 | 445.3
Airframes- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 164.2 | 106.1 | 334.1 | 199.8
Defense [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 101.7 | 81.6 | 196.6 | 158.1
Energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 179.5 | 200.3 | 389.7 | 360.0
Oil & Gas [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 111.3 | 125.2 | 238.8 | 228.3
Specialty Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 68.2 | 75.1 | 150.9 | 131.7
Automotive Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 52.8 | 75.5 | 112.2 | 166.5
Electronic Devices Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 36.0 | 49.4 | 70.4 | 101.0
Construction Mining Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 48.4 | 39.9 | 88.8 | 91.9
Food Equipment and Appliances Market |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 20.9 | 62.7 | 42.4 | 96.7
Medical Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 41.9 | 39.5 | 76.9 | 75.7
Other Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 59.7 | 55.8 | 121.2 | 98.6
Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,176.2 | 1,062.9 | 2,331.6 | 1,979.3
Operating Segments | High Performance Materials & Components |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 562.8 | $ 439.8 | $ 1,092.4 | $ 820.6
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 | 49.00% | 48.00% | 47.00% | 48.00%
Operating Segments | High Performance Materials & Components | Precision and Engineered Strip [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 1.00% | 0.00% | 1.00% | 0.00%
Operating Segments | High Performance Materials & Components | Precision Forgings, Casting and Components [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 33.00% | 35.00% | 33.00% | 35.00%
Operating Segments | High Performance Materials & Components | Titanium and Titanium-based Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 17.00% | 17.00% | 19.00% | 17.00%
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 | $ 222.0 | $ 179.8 | $ 418.5 | $ 336.2
Operating Segments | High Performance Materials & Components | Asia [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 51.0 | 50.5 | 95.0 | 94.7
Operating Segments | High Performance Materials & Components | Europe [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 207.8 | 135.0 | 402.0 | 256.3
Operating Segments | High Performance Materials & Components | CANADA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 16.6 | 12.7 | 28.6 | 23.0
Operating Segments | High Performance Materials & Components | South America, Middle East, and Other [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 29.7 | 18.1 | 54.1 | 27.5
Operating Segments | High Performance Materials & Components | Aerospace and Defense Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 436.2 | 316.0 | 831.6 | 573.6
Operating Segments | High Performance Materials & Components | Jet Engines- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 319.2 | 231.4 | 601.7 | 410.4
Operating Segments | High Performance Materials & Components | Airframes- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 67.0 | 43.9 | 138.0 | 81.1
Operating Segments | High Performance Materials & Components | Defense [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 50.0 | 40.7 | 91.9 | 82.1
Operating Segments | High Performance Materials & Components | Energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 33.6 | 39.6 | 60.9 | 86.8
Operating Segments | High Performance Materials & Components | Oil & Gas [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 3.7 | 8.1 | 6.1 | 25.2
Operating Segments | High Performance Materials & Components | Specialty Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 29.9 | 31.5 | 54.8 | 61.6
Operating Segments | High Performance Materials & Components | Automotive Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 6.0 | 2.3 | 12.3 | 5.2
Operating Segments | High Performance Materials & Components | Electronic Devices Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 0.7 | 0.7 | 1.2 | 1.2
Operating Segments | High Performance Materials & Components | Construction Mining Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 11.0 | 7.9 | 19.2 | 16.3
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 | 24.3 | 16.8 | 41.8 | 30.0
Operating Segments | High Performance Materials & Components | Other Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 15.3 | 12.8 | 31.2 | 24.6
Operating Segments | Advanced Alloys & Solutions |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 613.4 | $ 623.1 | $ 1,239.2 | $ 1,158.7
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 | 55.00% | 55.00% | 57.00% | 54.00%
Operating Segments | Advanced Alloys & Solutions | Precision and Engineered Strip [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 18.00% | 24.00% | 18.00% | 26.00%
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 | 11.00% | 6.00% | 10.00% | 6.00%
Operating Segments | Advanced Alloys & Solutions | Zirconium and Related Alloys [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Percent of revenue | 16.00% | 15.00% | 15.00% | 14.00%
Operating Segments | Advanced Alloys & Solutions | UNITED STATES |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 346.3 | $ 388.8 | $ 738.1 | $ 710.1
Operating Segments | Advanced Alloys & Solutions | Asia [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 103.5 | 104.4 | 213.0 | 219.5
Operating Segments | Advanced Alloys & Solutions | Europe [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 43.6 | 48.8 | 88.0 | 87.4
Operating Segments | Advanced Alloys & Solutions | CANADA |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 13.3 | 11.7 | 24.5 | 20.4
Operating Segments | Advanced Alloys & Solutions | South America, Middle East, and Other [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 12.2 | 9.7 | 22.3 | 18.5
Operating Segments | Advanced Alloys & Solutions | Aerospace and Defense Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 170.6 | 120.4 | 350.9 | 229.6
Operating Segments | Advanced Alloys & Solutions | Jet Engines- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 21.7 | 17.3 | 50.1 | 34.9
Operating Segments | Advanced Alloys & Solutions | Airframes- Commercial [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 97.2 | 62.2 | 196.1 | 118.7
Operating Segments | Advanced Alloys & Solutions | Defense [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 51.7 | 40.9 | 104.7 | 76.0
Operating Segments | Advanced Alloys & Solutions | Energy |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 145.9 | 160.7 | 328.8 | 273.2
Operating Segments | Advanced Alloys & Solutions | Oil & Gas [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 107.6 | 117.1 | 232.7 | 203.1
Operating Segments | Advanced Alloys & Solutions | Specialty Energy [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 38.3 | 43.6 | 96.1 | 70.1
Operating Segments | Advanced Alloys & Solutions | Automotive Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 46.8 | 73.2 | 99.9 | 161.3
Operating Segments | Advanced Alloys & Solutions | Electronic Devices Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 35.3 | 48.7 | 69.2 | 99.8
Operating Segments | Advanced Alloys & Solutions | Construction Mining Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 37.4 | 32.0 | 69.6 | 75.6
Operating Segments | Advanced Alloys & Solutions | Food Equipment and Appliances Market |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 20.9 | 62.7 | 42.4 | 96.7
Operating Segments | Advanced Alloys & Solutions | Medical Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 17.6 | 22.7 | 35.1 | 45.7
Operating Segments | Advanced Alloys & Solutions | Other Market [Member] |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 44.4 | 43.0 | 90.0 | 74.0
External Customers | Operating Segments |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 1,046.0 | 959.5 | 2,084.1 | 1,793.6
External Customers | Operating Segments | High Performance Materials & Components |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | 527.1 | 396.1 | 998.2 | 737.7
External Customers | Operating Segments | Advanced Alloys & Solutions |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue | $ 518.9 | $ 563.4 | $ 1,085.9 | $ 1,055.9

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