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Goodwill and Other Intangible Assets - Goodwill (Details) | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Aug. 13, 2021 USD ($) | Jun. 30, 2020 | Mar. 31, 2020 USD ($) | Jun. 03, 2019 USD ($)
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill | $ 227,900,000 | $ 240,700,000 |  |  |  |  |
Period increase (decrease) in goodwill | (12,800,000) |  |  |  |  |  |
Impairment of goodwill | 0 | (287,000,000) | $ 0 |  |  |  |
Accumulated goodwill impairment | $ 528,000,000 | $ 528,000,000 | $ 241,000,000 |  |  |  |
Flowform Products |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill |  |  |  | $ 12,200,000 |  |  |
Weighted average cost of capital | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill, fair value measurement input | 0.113 |  |  |  |  |  |
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 |  |  |  |  |  |
High Performance Materials & Components |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill | $ 227,900,000 |  |  |  |  |  |
Impairment of goodwill | 0 |  |  |  |  |  |
Goodwill, Foreign Currency Translation Gain (Loss) | (600,000) |  |  |  |  |  |
Forged Products |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill | $ 161,200,000 |  |  |  |  | $ 460,400,000 | $ 10,400,000
Percentage of fair value in excess of carrying value | 40.00% |  | 30.00% |  |  |  |
Forged Products | Weighted average cost of capital | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill, fair value measurement input |  |  |  |  | 0.116 |  |
Forged Products | Long-term growth rate | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill, fair value measurement input |  |  |  |  | 0.035 |  |
Specialty Materials [Member] |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill | $ 66,700,000 |  |  |  |  |  |

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