v3.20.2

Contingencies and Commitments​ (Details) |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 06, 2019 plaintiff | Sep. 15, 2017 executive | Jun. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) firefighters policeOfficers | Sep. 30, 2020 USD ($) firefighters policeOfficers | Jun. 26, 2020 claimants | Jun. 12, 2020 firefighters policeOfficers claimants | Jun. 11, 2020 firefighters | Dec. 31, 2019 USD ($)
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  | $ 181,000,000 | $ 181,000,000 |  |  |  | $ 208,000,000
Environmental remediation, current |  |  |  | 97,000,000 | 97,000,000 |  |  |  | 83,000,000
Environmental remediation, payments |  |  |  | 33,000,000 | 54,000,000 |  |  |  |
Accrual for Environmental Loss Contingencies, Increase (Decrease) for Acquisitions and Divestitures |  |  |  |  | 13,000,000 |  |  |  |
Accrual for Environmental Loss Contingencies, Period Increase (Decrease) |  |  |  | $ 1,000,000 | $ 3,000,000 |  |  |  |
Loss Contingency, Number of Firefighters | firefighters |  |  |  | 1 | 1 |  | 2 | 80 |
Accrual for Environmental Loss Contingencies, Revision in Estimates |  |  |  |  | $ 5,000,000 |  |  |  |
Loss Contingency, Number of Police Officers | policeOfficers |  |  |  | 37 | 37 |  | 27 |  |
Site Remediation Systems [Member] |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  | $ (1,000,000) |  |  |  |  |
Unpaid Invoices [Member] |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Accounts Payable, Trade |  |  |  |  |  |  |  |  | 22,000,000
Other Environmental [Member] |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Accrual for Environmental Loss Contingencies, Period Increase (Decrease) |  |  |  |  | $ (5,000,000) |  |  |  |
Aluminum Rolling Mill in Itapissuma, Brazil |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Environmental remediation, additions |  |  |  |  | (1,000,000) |  |  |  |
Behrens v. Arconic |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Number of plaintiffs | plaintiff | 247 |  |  |  |  |  |  |  |
Sullivan v. Arconic |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Number of former executives | executive |  | 3 |  |  |  |  |  |  |
Birnberg Peirce Ltd [Member] |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Loss Contingency, Number of Claimants | claimants |  |  |  |  |  |  | 4 |  |
Howe & Co Solicitors [Member] |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Loss Contingency, Number of Claimants | claimants |  |  |  |  |  |  | 2 |  |
Russell-Cooke LLP [Member] |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Loss Contingency, Number of Claimants | claimants |  |  |  |  |  | 3 |  |  |
Massena West, NY |  |  |  |  |  |  |  |  |
Site Contingency [Line Items] |  |  |  |  |  |  |  |  |
Environmental remediation |  |  |  | $ 131,000,000 | $ 131,000,000 |  |  |  | 171,000,000
Environmental remediation, additions |  |  | $ (25,000,000) |  |  |  |  |  |
Accounts Payable, Trade |  |  |  |  |  |  |  |  | $ 21,000,000

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