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Commitments and Contingencies - DOE Project (Details) - Task order to provide deactivation, demolition and removal services at New York State project site - USD ($) $ in Millions | Jan. 31, 2020 | Dec. 06, 2019 | Sep. 30, 2023 | Dec. 31, 2014
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Commitments and Contingencies |  |  |  |
Percentage of claim recoveries due to purchaser | 10.00% |  |  |
Percentage of claim recoveries due to seller | 90.00% |  |  |
Former Affiliate |  |  |  |
Commitments and Contingencies |  |  |  |
Minimum project cost to pay |  |  | $ 146.0 |
Department of Energy |  |  |  |
Commitments and Contingencies |  |  |  |
Maximum project cost to pay |  |  | 106.0 |
Additional fees on changed work scope |  | $ 60.4 |  | $ 103.0
Former Affiliate and DOE |  |  |  |
Commitments and Contingencies |  |  |  |
Maximum project cost to pay |  |  | 146.0 |
Minimum project cost to pay |  |  | $ 106.0 |
Former Affiliate | Department of Energy | Minimum |  |  |  |
Commitments and Contingencies |  |  |  |
Damages sought |  | 148.5 |  |
Former Affiliate | Department of Energy | Maximum |  |  |  |
Commitments and Contingencies |  |  |  |
Damages sought |  | $ 329.4 |  |

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