| **Business Combinations - Table 1 (Details) (USD $)In Millions, unless otherwise specified** |        |        |        | 3 Months Ended |        | 3 Months Ended |        | 3 Months Ended |        |
|----------------------------------------------------------------------------------------------|--------|--------|--------|----------------|--------|----------------|--------|----------------|--------|
||
| **Business Acquisition [Line Items]**                                                        |   |   |   |           |   |           |   |           |   |
| Property and equipment, net                                                                  |   | $ 11.3 |   |           |   |           |   |           |   |
| Identifiable intangible assets                                                               |   |   |   |           | 0.1    |           | 0.9    |           | 3.3    |
| Goodwill                                                                                     | 457.2  | 13.7   | 437.3  |           |   |           |   |           |   |
| Total assets acquired                                                                        |   | 29.3   |   |           |   |           |   |           |   |
| Total current liabilities assumed                                                            |   | (0.4)  |   |           |   |           |   |           |   |
| Total assets acquired                                                                        |   | $ 28.9 |   |           |   |           |   |           |   |
| **Useful Lives of Acquired Finite-Lived Intangible Assets [Abstract]**                       |   |   |   |           |   |           |   |           |   |
| Acquired Finite-lived Intangible Asset, Weighted Average Useful Life                         |   |   |   | 5 years        |   | 20 years       |   | 20 years       |   |

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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Amount of assets acquired at the acquisition date.
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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.
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The amount of identifiable intangible assets recognized as of the acquisition date.
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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.
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| - Definition
The amount of property, plant, and equipment recognized as of the acquisition date.
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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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