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v3.25.1

Contingencies, Commitments and Other Liabilities (Details) € in Millions, $ in Millions |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Mar. 31, 2023 USD ($) | Mar. 31, 2023 EUR (€) | Mar. 31, 2025 USD ($) location | Dec. 31, 2024 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2023 EUR (€) | Jul. 23, 2024 USD ($) | Jul. 23, 2024 EUR (€)
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Number of cleanup locations | location |  |  | 30 |  |  |  |  |  |
Remediation reserve balance |  |  | $ 16 | $ 19 |  |  |  |  |
Remediation reserve balance, classified as a current liability |  |  | 7 | 10 |  |  |  |  |
Payments related to remediation expenses applied against the reserve (less than in second quarter) |  |  | 3 |  | $ 1 |  |  |  |
Guarantees of third party related to project financing |  |  | 6 |  |  |  |  |  |
Combined fair value of guarantees |  |  | $ 6 | 6 |  |  |  |  |
Indemnification of liability (as a percent) |  |  | 50.00% |  |  |  |  |  |
Coverage limit |  |  |  | $ 80 |  |  |  |  |
Total amount committed under outstanding surety bonds |  |  | $ 45 |  |  |  |  |  |
Surety bonds, amount outstanding |  |  | $ 21 |  |  |  |  |  |
Termination notice period (in days) |  |  | 30 days |  |  |  |  |  |
Payment timing (in days) |  |  | 120 days |  |  |  |  |  |
Supplier Finance Program, Obligation, Current, Statement of Financial Position [Extensible Enumeration] |  |  | Accounts payable, trade (P) | Accounts payable, trade (P) |  |  |  |  |
Supplier invoices subject to future payment |  |  | $ 264 | $ 268 |  |  |  |  |
Letter of Credit |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  | 81 |  |  |  |  |  |
Other Noncurrent Liabilities and Deferred Credits | Separation Agreement |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Guarantees of third party related to project financing |  |  | $ 1,121 | $ 1,121 |  |  |  |  |
Foreign Tax Authority | Ministry of the Economy, Finance and Industry, France | Tax Years 2010 Through 2012 |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Income tax assessment, estimate of possible loss | $ 17 | € 16 |  |  |  |  |  |  |
Income tax assessment, amount of penalties cancelled |  |  |  |  |  |  |  | $ 7 | € 7
Income tax reserve |  |  |  |  |  | $ 21 | € 19 |  |
Recurring Costs of Managing Hazardous Substances and Environmental Programs |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Percentage of cost of goods sold (as a percent) |  |  | 1.00% |  |  |  |  |  |
Income Tax and Interest | Foreign Tax Authority | Ministry of the Economy, Finance and Industry, France | Tax Years 2010 Through 2012 |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Income tax assessment, estimate of possible loss | 10 | 9 |  |  |  |  |  |  |
Income Tax Penalties | Foreign Tax Authority | Ministry of the Economy, Finance and Industry, France | Tax Years 2010 Through 2012 |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Income tax assessment, estimate of possible loss | 7 | 7 |  |  |  |  |  |  |
Additional Interest on Income Tax | Foreign Tax Authority | Ministry of the Economy, Finance and Industry, France | Tax Years 2010 Through 2012 |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Income tax assessment, estimate of possible loss | $ 2 | € 2 |  |  |  |  |  |  |
Alcoa Corporation Workers Compensation Claims |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Letters of credit, total amount outstanding |  |  | $ 48 |  |  |  |  |  |
Arconic Corporation Environmental Obligations |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Letters of credit, total amount outstanding |  |  | 9 |  |  |  |  |  |
Arconic Corporation Environmental Obligations | Letter of Credit |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Decrease in letters of credit |  |  | $ 8 |  |  |  |  |  |

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