v3.23.2

Contingencies and Commitments​ (Details) $ in Millions |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 12 Months Ended | 37 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 06, 2019 plaintiff | Sep. 15, 2017 executive | Jul. 31, 2023 USD ($) | Jul. 31, 2022 USD ($) | Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jun. 30, 2023 USD ($) claimant | Jun. 30, 2023 USD ($) claimant
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  |  | $ 72.0 |  | $ 72.0 | $ 85.0 | $ 72.0 | $ 72.0
Environmental remediation, current |  |  |  |  | 34.0 |  | 34.0 | 40.0 | $ 34.0 | $ 34.0
Environmental remediation, payments |  |  |  |  | 4.0 |  | 14.0 |  |  |
Behrens v. Arconic |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of plaintiffs | plaintiff | 247 |  |  |  |  |  |  |  |  |
Sullivan v. Arconic |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of former executives | executive |  | 3 |  |  |  |  |  |  |  |
Damage from Fire, Explosion or Other Hazard | Grenfell Tower Fire, Survivors And Estates Of Decedents |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of plaintiffs | claimant |  |  |  |  |  |  |  |  |  | 1,000
Loss Contingency, Receivable, Additions |  |  |  |  |  |  |  | 53.0 |  |
Loss Contingency Accrual, Payments |  |  |  |  |  | $ 43.0 |  |  |  |
Loss Contingency, Receivable, Proceeds |  |  |  |  |  | $ 41.0 |  |  |  |
Damage from Fire, Explosion or Other Hazard | Grenfell Tower Fire, Survivors And Estates Of Decedents | Subsequent events |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Loss Contingency Accrual, Payments |  |  | $ 8.0 |  |  |  |  |  |  |
Damage from Fire, Explosion or Other Hazard | Grenfell Tower Fire, Survivors And Estates Of Decedents | Other Current Liabilities |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Loss Contingency Accrual, Provision |  |  |  |  |  |  |  | 61.0 |  |
Loss Contingency Accrual |  |  |  |  |  |  |  | 61.0 |  |
Damage from Fire, Explosion or Other Hazard | Grenfell Tower Fire, Survivors And Estates Of Decedents | Prepaid Expenses and Other Current Assets |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Loss Contingency, Receivable |  |  |  |  |  |  |  | 53.0 |  |
Damage from Fire, Explosion or Other Hazard | Grenfell Tower Fire, Emergency Responders |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Number of plaintiffs | claimant |  |  |  |  |  |  |  |  | 150 |
Damage from Fire, Explosion or Other Hazard | Sullivan v. Arconic |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Loss Contingency Accrual, Provision |  |  |  |  |  |  | 74.0 |  |  |
Loss Contingency, Receivable, Additions |  |  |  |  |  |  | 74.0 |  |  |
Damage from Fire, Explosion or Other Hazard | Sullivan v. Arconic | Other Current Liabilities |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Loss Contingency Accrual |  |  |  |  | 74.0 |  | 74.0 |  | $ 74.0 | $ 74.0
Damage from Fire, Explosion or Other Hazard | Sullivan v. Arconic | Prepaid Expenses and Other Current Assets |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |
Loss Contingency, Receivable |  |  |  |  | 74.0 |  | 74.0 |  | 74.0 | 74.0
Massena West, NY |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  |  | 30.0 |  | 30.0 | 38.0 | 30.0 | 30.0
Massena West, NY | Environmental Issue [Member] |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  | (13.0) |  |
Massena West, NY | Environmental Issue [Member] | Scenario, Plan |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  | $ 22.0 |  |  |  |  |  |
Active Remediation Systems and Monitoring And Inspection Programs At Several Sites |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  |  |  | 1.0 |  |  |
Second Largest Reserve |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  |  | $ 6.0 |  | $ 6.0 |  | $ 6.0 | $ 6.0
Davenport, IA |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  |  |  |  | (0.5) |  |
Davenport, IA | Minimum |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated Future Capital Expenditures |  |  |  |  |  |  |  | 25.0 |  |
Davenport, IA | Maximum |  |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated Future Capital Expenditures |  |  |  |  |  |  |  | $ 30.0 |  |

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