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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019
Environmental Contingency |  |
Short-term environmental accrual | $ 6.6 | $ 5.5
Environmental accrual | $ 18.2 |
Expected period related to remediation expenditures for environmental contingencies period | 30 years |
Potential increase in environmental costs | $ 11.6 |
Time period within which recorded estimate of its obligation may change | 12 months |
Comprehensive Environmental Response, Compensation and Liability Act |  |
Environmental Contingency |  |
Short-term environmental accrual | $ 1.9 |
Minimum |  |
Environmental Contingency |  |
Period for final feasibility study | 12 months |
Maximum |  |
Environmental Contingency |  |
Period for final feasibility study | 24 months |

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