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v3.21.2

Contingencies and Commitments (Details) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2021 USD ($) location | Dec. 31, 2020 USD ($) | Jun. 26, 2020 USD ($) entity
Loss Contingencies [Line Items] |  |  |  |
Number of cleanup locations | location |  | 30 |  |
Remediation reserve balance | $ 10 | $ 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 | 18 | 18 |  |
Combined fair value of guarantees | 6 | 6 | 12 |
Total amount committed under outstanding surety bonds | 46 | 46 |  |
Surety bonds, amount outstanding | 25 | 25 |  |
Lehman Brothers International (Europe) (“LBIE”) Claims |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Number of entities | entity |  |  |  | 2
Estimate of claim |  |  |  | $ 64
Bank Loan Obligations |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Letters of credit, total amount | 133 | 133 |  |
Other Noncurrent Liabilities and Deferred Credits | Separation Agreement |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Guarantees of third party related to project financing | 1,435 | 1,435 | $ 1,398 |
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 | 23 | 23 |  |
Arconic Corporation Environmental Obligations | Letters Of Credit, Pending Cancellation |  |  |  |
Loss Contingencies [Line Items] |  |  |  |
Letters of credit, total amount outstanding | $ 6 | $ 6 |  |
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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