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ACCOUNTING POLICIES (Tables) | 12 Months Ended
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Dec. 31, 2023
Accounting Policies [Abstract] |
Asset retirement obligation activity | The activities of our asset retirement obligations were as follows:
| December 31,
| 2023 |  | 2022
Asset Retirement Obligation Activity | ($ in millions)
Beginning balance | $ | 66.3 |  |  | $ | 70.2 |
Accretion | 3.3 |  |  | 3.8 |
Spending | (5.0) |  |  | (8.7) |
Adjustments | 8.2 |  |  | 1.0 |
Ending balance | $ | 72.8 |  |  | $ | 66.3 |

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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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