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Contingencies and Commitments (Details) € in Millions, $ in Millions |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Mar. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Mar. 31, 2023 USD ($) location | Mar. 31, 2023 EUR (€) location | Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) | Jun. 26, 2020 USD ($) entity derivative
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Number of cleanup locations | location |  |  | 30 | 30 |  |  |
Remediation reserve balance |  | $ 16 | $ 17 |  |  | $ 16 |
Remediation reserve balance, classified as a current liability |  | 6 | 7 |  |  | 6 |
Payments related to remediation expenses applied against the reserve (less than) |  |  | 1 |  |  |  |
Assessment amount |  |  | 19 | € 18 |  |  |
Income tax reserve |  |  | 20 | € 19 | $ 0 |  |
Judgement from legal proceedings | $ 74 |  |  |  |  |  |
Guarantees of third party related to project financing |  |  | 13 |  |  |  |
Combined fair value of guarantees |  | 6 | 6 |  |  | 6 |
Coverage limit |  | 80 |  |  |  |  |
Total amount committed under outstanding surety bonds |  |  | 43 |  |  |  |
Surety bonds, amount outstanding |  |  | 22 |  |  |  |
Bank Loan Obligations |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Letters of credit, total amount |  |  | 119 |  |  |  |
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] |  |  |  |  |  |  |
Number of entities | entity |  |  |  |  |  |  | 2
Number of derivative transactions | derivative |  |  |  |  |  |  | 2
Estimate of claim |  |  |  |  |  |  | $ 64
Extension period |  |  |  |  |  | 3 years |
Amount reserved |  |  | 65 |  |  |  |
Alcoa Corporation Workers Compensation Claims |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Letters of credit, total amount outstanding |  |  | 52 |  |  |  |
Arconic Corporation Environmental Obligations |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Letters of credit, total amount outstanding |  |  | $ 17 |  |  |  |
Maximum | Recurring Costs of Managing Hazardous Substances and Environmental Programs |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of cost of goods sold (percent) |  |  | 1.00% | 1.00% |  |  |

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