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v3.21.2

Contingencies and Commitments (Details) $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2021 USD ($) location | Dec. 31, 2020 USD ($) | Jun. 26, 2020 USD ($) entity
Loss Contingencies [Line Items] |  |  |  |
Number of cleanup locations | location |  | 30 |  |
Remediation reserve balance | $ 12 | $ 12 | $ 10 |
Remediation reserve balance, classified as a current liability | 6 | 6 | 5 |
Payments related to remediation expenses applied against the reserve | 1 |  |  |
Guarantees of third party related to project financing | 16 | 16 |  |
Combined fair value of guarantees | 6 | 6 | 12 |
Total amount committed under outstanding surety bonds | 46 | 46 |  |
Surety bonds, amount outstanding | 25 | 25 |  |
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 | 1,406 | 1,406 | $ 1,398 |
Lehman Brothers International (Europe) (“LBIE”) Claims |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Number of entities | entity |  |  |  | 2
Estimate of claim |  |  |  | $ 64
Alcoa Corporation Workers Compensation Claims |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Letters of credit, total amount outstanding | 53 | 53 |  |
Arconic Corporation Environmental Obligations |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Letters of credit, total amount outstanding | 17 | 17 |  |
Arconic Corporation Environmental Obligations | Letters Of Credit, Pending Cancellation |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Letters of credit, total amount outstanding | $ 1 | $ 1 |  |
Maximum | Recurring Costs of Managing Hazardous Substances and Environmental Programs |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Percentage of cost of goods sold (percent) |  | 1.00% |  |

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