| **Business Combinations - Table 3 (Details) - USD ($) $ in Millions**                                                 | Sep. 30, 2016 | Dec. 31, 2015 |
|-----------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Business Acquisition [Line Items]**                                                                                 |          |          |
| Goodwill                                                                                                              | $ 1,915.6     | $ 1,890.1     |
| Home Health and Hospice Segment [Member] | Camellia, Advantage and Serenity [Member]                                  |          |          |
| **Business Acquisition [Line Items]**                                                                                 |          |          |
| Goodwill                                                                                                              | 16.3          |          |
| Total assets acquired                                                                                                 | 19.7          |          |
| Total liabilities assumed                                                                                             | (0.1)         |          |
| Net assets acquired                                                                                                   | 19.6          |          |
| Home Health and Hospice Segment [Member] | Camellia, Advantage and Serenity [Member] | Noncompete Agreements [Member] |          |          |
| **Business Acquisition [Line Items]**                                                                                 |          |          |
| Identifiable intangible assets                                                                                        | 0.2           |          |
| Home Health and Hospice Segment [Member] | Camellia, Advantage and Serenity [Member] | Trade Names [Member]           |          |          |
| **Business Acquisition [Line Items]**                                                                                 |          |          |
| Identifiable intangible assets                                                                                        | 0.2           |          |
| Home Health and Hospice Segment [Member] | Camellia, Advantage and Serenity [Member] | Certificate of Need [Member]   |          |          |
| **Business Acquisition [Line Items]**                                                                                 |          |          |
| Identifiable intangible assets                                                                                        | 1.9           |          |
| Home Health and Hospice Segment [Member] | Camellia, Advantage and Serenity [Member] | License [Member]               |          |          |
| **Business Acquisition [Line Items]**                                                                                 |          |          |
| Identifiable intangible assets                                                                                        | $ 1.1         |          |

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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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