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Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2019
Accounting Policies [Abstract] |
Net gain on disposition of assets | The following table presents the net gain on asset dispositions for the years ended December 31 (in millions):
| 2024 |  | 2023 |  | 2022
Net disposition gains | $ | 122.0 |  |  | $ | 119.8 |  |  | $ | 104.1 |
Residual sharing income | 0.5 |  |  | 0.9 |  |  | 5.6 |
Non-remarketing net disposition gains | 15.8 |  |  | 11.1 |  |  | 17.1 |
Asset impairments (1) | — |  |  | (1.5) |  |  | (48.9) |
Net gain on asset dispositions | $ | 138.3 |  |  | $ | 130.3 |  |  | $ | 77.9 |
__________ (1) See "Note 10. Asset Impairments and Assets Held for Sale" for further information about asset impairment losses.

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