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v3.23.3

Contingencies and Commitments (Details) € in Millions, $ in Millions |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 15, 2023 USD ($) installment | Jul. 31, 2024 USD ($) | Jul. 31, 2023 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2023 EUR (€) | Jun. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) location | Sep. 30, 2022 USD ($) | Mar. 31, 2023 EUR (€) | Jun. 26, 2020 derivative entity
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of cleanup locations | location |  |  |  |  |  |  |  |  |  | 30 |  |  |
Remediation reserve balance |  |  |  |  | $ 16 | $ 17 |  |  |  | $ 17 |  |  |
Remediation reserve balance, classified as a current liability |  |  |  |  | 6 | 6 |  |  |  | 6 |  |  |
Payments related to remediation expenses applied against the reserve |  |  |  |  |  | 2 |  |  | $ 1 | 4 | $ 1 |  |
Income tax reserve |  |  |  |  |  | 0 |  |  | 0 | 20 | 0 |  |
Judgement from legal proceedings |  |  |  | $ 74 |  |  |  |  |  |  |  |  |
Reversal of previously recorded litigation amount |  |  |  |  |  |  |  | $ 25 |  | 25 |  |  |
Guarantees of third party related to project financing |  |  |  |  |  | 20 |  |  |  | 20 |  |  |
Combined fair value of guarantees |  |  |  |  | 6 | 6 |  |  |  | 6 |  |  |
Coverage limit |  |  |  |  | 80 |  |  |  |  |  |  |  |
Total amount committed under outstanding surety bonds |  |  |  |  |  | 42 |  |  |  | 42 |  |  |
Surety bonds, amount outstanding |  |  |  |  |  | 21 |  |  |  | 21 |  |  |
Bank Loan Obligations |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Letters of credit, total amount |  |  |  |  |  | 116 |  |  |  | 116 |  |  |
Other Noncurrent Liabilities and Deferred Credits | Separation Agreement |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantees of third party related to project financing |  |  |  |  | $ 1,040 | 1,040 |  |  |  | 1,040 |  |  |
Lehman Brothers International (Europe) (“LBIE”) Claims |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Judgement from legal proceedings | $ 40 |  |  |  |  |  |  |  |  |  |  |  |
Number of entities | entity |  |  |  |  |  |  |  |  |  |  |  |  | 2
Number of derivative transactions | derivative |  |  |  |  |  |  |  |  |  |  |  |  | 2
Amount reserved |  |  |  |  |  |  |  |  | $ 65 |  | $ 65 |  |
Number of installment payments | installment | 2 |  |  |  |  |  |  |  |  |  |  |  |
Payments for legal settlements |  |  | $ 15 |  |  |  |  |  |  |  |  |  |
Lehman Brothers International (Europe) (“LBIE”) Claims | Subsequent Event | Forecast |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Payments for legal settlements |  | $ 25 |  |  |  |  |  |  |  |  |  |  |
Foreign Tax Authority | Ministry of the Economy, Finance and Industry, France | Tax Years 2010 Through 2012 |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Assessment amount |  |  |  | $ 19 |  |  |  |  |  |  |  | € 18 |
Income tax reserve |  |  |  |  |  | 20 | € 19 |  |  |  |  |  |
Alcoa Corporation Workers Compensation Claims |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Letters of credit, total amount outstanding |  |  |  |  |  | 52 |  |  |  | 52 |  |  |
Arconic Corporation Environmental Obligations |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Letters of credit, total amount outstanding |  |  |  |  |  | $ 17 |  |  |  | $ 17 |  |  |
Maximum | Recurring Costs of Managing Hazardous Substances and Environmental Programs |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of cost of goods sold (as a percent) |  |  |  |  |  |  |  |  |  | 1.00% |  |  |

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