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Commitments and Contingencies - Refinery Turnaround Project (Details) - Refinery Turnaround Project - USD ($) $ in Millions | 1 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Apr. 30, 2019 | Mar. 31, 2019 | Mar. 31, 2024
Commitments and Contingencies |  |  |  |
Amount of work outside original contract |  |  |  | $ 90.0
Payment entitled to |  |  |  | $ 144.0
Construction lien against the refinery for unpaid labor and materials costs |  | $ 132.0 |  |
A Refinery in Montana |  |  |  |
Commitments and Contingencies |  |  |  |
Damages sought, counter party | $ 93.0 |  | $ 79.0 |

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