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v3.22.4

Restructuring Costs (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) employee | Dec. 31, 2021 USD ($) employee | Dec. 31, 2020 USD ($) position
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring and other charges (credits) | $ 23.7 | $ (10.5) | $ 1,132.1
Non-cash restructuring charges | 0.0 | 0.0 | 1,041.5
Restructuring charges (credits) | (4.8) | (11.3) | 1,107.5
Severance costs |  |  | $ 60.5
Restructuring and Related Cost, Expected Number of Positions Eliminated | position |  |  | 1,400
Inventory write-down |  | 0.8 | $ 7.2
Termination benefits |  |  | 17.4
Restructuring Reserve [Roll Forward] |  |  |
Other nonoperating income (expense), litigation reserve | $ (28.5) | 0.0 | 0.0
Brackenridge PA Operations |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Asset impairment charges |  |  | 1,032.6
Fair value |  |  | $ 354.0
Brackenridge PA Operations | Weighted average cost of capital | Fair Value, Inputs, Level 3 [Member] |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Long-Lived Asset, Measurement Input |  |  | 0.093
Brackenridge PA Operations | Long-term growth rate | Fair Value, Inputs, Level 3 [Member] |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Long-Lived Asset, Measurement Input |  |  | 0.02
Various AA&S Segment Operations |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Asset impairment charges |  |  | $ 8.9
Facility Idling |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring charges (credits) |  |  | 5.5
Restructuring Reserve [Roll Forward] |  |  |
Restructuring Charges |  | $ 0.7 |
Employee Severance |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Reduction in severance related reserves, workforce | employee | 110 | 350 |
Restructuring Reserve [Roll Forward] |  |  |
Restructuring Reserve, Beginning Balance | $ 17.7 | $ 43.4 | 4.5
Restructuring Charges | (4.8) | (12.0) | 60.5
Payments for Restructuring | (3.1) | (13.7) | (21.6)
Restructuring Reserve, Ending Balance | 9.8 | 17.7 | $ 43.4
Other Current Liabilities [Member] |  |  |
Restructuring Reserve [Roll Forward] |  |  |
Restructuring Reserve, Beginning Balance | 11.4 |  |
Restructuring Reserve, Ending Balance | 5.4 | 11.4 |
Other Noncurrent Liabilities [Member] |  |  |
Restructuring Reserve [Roll Forward] |  |  |
Restructuring Reserve, Beginning Balance | 6.3 |  |
Restructuring Reserve, Ending Balance | $ 4.4 | $ 6.3 |

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