| **Goodwill and Other Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Millions** | Dec. 31, 2016 | Dec. 31, 2015 |
|------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | $ 667.2       | $ 627.8       |
| Accumulated Amortization                                                                             | (255.9)       | (208.4)       |
| Net                                                                                                  | 411.3         | 419.4         |
| Certificate of Need [Member]                                                                         |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 98.6          | 93.9          |
| Accumulated Amortization                                                                             | (12.9)        | (6.9)         |
| Net                                                                                                  | 85.7          | 87.0          |
| Licenses [Member]                                                                                    |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 142.0         | 138.9         |
| Accumulated Amortization                                                                             | (62.1)        | (53.7)        |
| Net                                                                                                  | 79.9          | 85.2          |
| Noncompete Agreements [Member]                                                                       |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 62.2          | 58.0          |
| Accumulated Amortization                                                                             | (47.3)        | (37.0)        |
| Net                                                                                                  | 14.9          | 21.0          |
| Trade Name - Encompass [Member]                                                                      |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 135.2         | 135.2         |
| Accumulated Amortization                                                                             | 0.0           | 0.0           |
| Net                                                                                                  | 135.2         | 135.2         |
| Trade Names [Member]                                                                                 |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 34.6          | 32.9          |
| Accumulated Amortization                                                                             | (13.9)        | (11.5)        |
| Net                                                                                                  | 20.7          | 21.4          |
| Internal-use Software [Member]                                                                       |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 181.4         | 155.7         |
| Accumulated Amortization                                                                             | (110.2)       | (90.5)        |
| Net                                                                                                  | 71.2          | 65.2          |
| Market Access Assets [Member]                                                                        |          |          |
| **Schedule of Intangible Assets by Major Class**                                                     |          |          |
| Gross Carrying Amount                                                                                | 13.2          | 13.2          |
| Accumulated Amortization                                                                             | (9.5)         | (8.8)         |
| Net                                                                                                  | $ 3.7         | $ 4.4         |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275
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| X                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
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