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Commitments and Contingencies (Tables) | 12 Months Ended
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Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract] |
Schedule of Changes in Asset Retirement Obligations | The following shows the changes in asset retirement obligations:
years ended December 31 (in millions) |  | 2023 |  |  | 2022 |  |  | 2021 |
Balance at beginning of year |  | $ | 380.0 |  |  | $ | 306.8 |  |  | $ | 153.8 |
Accretion expense |  |  | 10.9 |  |  |  | 10.6 |  |  |  | 7.2 |
Liabilities incurred and liabilities assumed in business combinations |  |  | 33.8 |  |  |  | 78.6 |  |  |  | 179.0 |
Liabilities settled |  |  | (27.7 | ) |  |  | (14.1 | ) |  |  | (5.2 | )
Revisions in estimated cash flows |  |  | (12.5 | ) |  |  | (3.1 | ) |  |  | 3.5 |
Liabilities reclassified from/(to) assets held for sale |  |  | 15.8 |  |  |  | 1.2 |  |  |  | (31.5 | )
Balance at end of year |  | $ | 400.3 |  |  | $ | 380.0 |  |  | $ | 306.8 |
Schedule of Contractual Purchase Commitments | The Company’s contractual purchase commitments as of December 31, 2023 are as follows:
(in millions) |  |  |
2024 |  | $ | 247.2 |
2025 |  |  | 39.1 |
2026 |  |  | 28.7 |
2027 |  |  | 14.1 |
2028 |  |  | 14.4 |
Thereafter |  |  | 51.7 |
Total |  | $ | 395.2 |
Schedule of Future Minimum Contracts of Affreightment and Royalty Commitments for All Noncancelable Agreements | Future minimum contracts of affreightment and royalty commitments for all noncancelable agreements that are not accounted for as leases on the Company’s consolidated balance sheet as of December 31, 2023 are as follows:
(in millions) |  | Contracts of Affreightment |  |  | Royalty Commitments |
2024 |  | $ | 16.9 |  |  | $ | 26.4 |
2025 |  |  | 17.1 |  |  |  | 14.1 |
2026 |  |  | 17.4 |  |  |  | 11.7 |
2027 |  |  | 17.7 |  |  |  | 11.2 |
2028 |  |  | — |  |  |  | 8.0 |
Thereafter |  |  | — |  |  |  | 77.4 |
Total |  | $ | 69.1 |  |  | $ | 148.8 |

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- Definition Tabular disclosure of key provisions of an arrangement under which the entity has agreed to purchase goods or services over a period of time greater than one year or the normal operating cycle, if longer, including the item for which expenditures will be made, minimum quantities, milestones, time period and committed amount. + References No definition available. + Details
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- Definition Tabular disclosure of the carrying amount of a liability for asset retirement obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 410 -SubTopic 20 -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481850/410-20-50-1 + Details
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