| **Investments In and Advances to Nonconsolidated Affiliates - Table 1 (Details) - USD ($) $ in Millions** | 3 Months Ended | 9 Months Ended |
|-----------------------------------------------------------------------------------------------------------|----------------|----------------|
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| **Investments in and Advances to Affiliates, Schedule of Investments [Abstract]**                         |           |           |   |   |
| Net operating revenues                                                                                    | $ 11.3         | $ 9.2          | $ 33.4 | $ 26.3 |
| Operating expenses                                                                                        | (6.0)          | (4.0)          | (18.1) | (11.7) |
| Income from continuing operations, net of tax                                                             | 5.2            | 5.1            | 15.2 | 13.8 |
| Net income                                                                                                | $ 5.2          | $ 5.1          | $ 15.2 | $ 13.8 |

| X                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of operating expense reported by an equity method investment of the entity.
+ References
No definition available.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of income (loss) from continuing operations reported by an equity method investee.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of net income (loss) reported by an equity method investment of the entity.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.
+ References
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| - References
No definition available.
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