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Commitments and Contingencies (Tables) | 12 Months Ended
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Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract] |
Summary of Activities Relating to Company's CARO Liabilities | The following table summarizes activity relating to CARO liabilities (in millions of dollars):
|  | Year Ended December 31, |
|  | 2023 |  |  | 2022 |  |  | 2021 |
Beginning balance |  | $ | 10.1 |  |  | $ | 7.2 |  |  | $ | 6.7 |
Liabilities added during the period |  |  | — |  |  |  | 2.3 |  |  |  | — |
Liabilities settled during the period |  |  | — |  |  |  | (0.1 | ) |  |  | (0.1 | )
Accretion expense |  |  | 0.8 |  |  |  | 0.7 |  |  |  | 0.6 |
Ending balance |  | $ | 10.9 |  |  | $ | 10.1 |  |  | $ | 7.2 |
Schedule of Changes in Environmental Contingencies | The following table presents the changes in our environmental accrual. We classify the short-term and long-term liabilities within Other accrued liabilities and Long-term liabilities, respectively, on our Consolidated Balance Sheets (in millions of dollars):
|  | Year Ended December 31, |
|  | 2023 |  |  | 2022 |  |  | 2021 |
Beginning balance |  | $ | 17.7 |  |  | $ | 16.8 |  |  | $ | 18.7 |
Additional accruals |  |  | 1.2 |  |  |  | 3.2 |  |  |  | 0.1 |
Less: expenditures |  |  | (1.9 | ) |  |  | (2.3 | ) |  |  | (2.0 | )
Ending balance |  | $ | 17.0 |  |  | $ | 17.7 |  |  | $ | 16.8 |

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- Definition Schedule of accrual for environmental loss contingencies. + References No definition available. + Details
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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481850/410-20-50-1 + Details
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