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Supplemental Financial Statement Information - Other Non-operating Income (Expense) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Other Nonoperating Income (Expense) [Abstract] |  |  |  |  |  |  |
Rent, royalty income and other income |  |  |  |  | $ 2.9 | $ 3.1 | $ 3.5
Gains from disposal of property, plant and equipment, net |  |  |  |  | 90.7 | 1.3 | 0.5
Income (loss) from equity method investments |  |  |  |  | (10.7) | (1.0) | 0.0
Loss on sale of businesses, net |  |  |  |  | (1.9) | 0.0 | 0.0
Gain on joint venture deconsolidation |  |  |  | $ 15.9 | 0.0 | 15.9 | 0.0
Non-cash joint venture impairment charge | $ (11.4) |  |  |  | (11.4) | 0.0 | 0.0
Other |  |  |  |  | 0.1 | 1.2 | 0.0
Other income, net |  |  |  |  | 69.7 | $ 20.5 | $ 4.0
Gain from sale of certain oil and gas rights |  | $ 62.4 | $ 29.3 |  | $ 91.7 |  |

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