| **Segment Reporting Segment Reporting - Table 1 (Details) - USD ($) $ in Millions** | 3 Months Ended | 6 Months Ended |
|-------------------------------------------------------------------------------------|----------------|----------------|
||
| **Segment Reporting Information [Line Items]**                                      |           |           |   |   |
| Net operating revenues                                                              | $ 920.7        | $ 764.4        | $ 1,830.5 | $ 1,505.0 |
| Provision for Doubtful Accounts                                                     | (15.4)         | (10.9)         | (31.9) | (22.5) |
| Net operating revenues less provision for doubtful accounts                         | 905.3          | 753.5          | 1,798.6 | 1,482.5 |
| **Costs and Expenses [Abstract]**                                                   |           |           |   |   |
| Salaries and benefits                                                               | 486.1          | 401.8          | 972.2 | 786.9 |
| Other operating expenses                                                            | 121.5          | 104.2          | 240.7 | 207.4 |
| Supplies                                                                            | 34.4           | 31.7           | 69.4 | 63.1 |
| Occupancy costs                                                                     | 17.9           | 12.5           | 35.9 | 24.6 |
| Total segment level operating expenses                                              | 738.9          | 615.1          | 1,471.7 | 1,223.6 |
| Other income                                                                        | (0.7)          | (3.0)          | (1.3) | (3.5) |
| Equity in net income of nonconsolidated affiliates                                  | (2.4)          | (2.3)          | (4.8) | (3.9) |
| Noncontrolling interest                                                             | (18.6)         | (17.3)         | (37.3) | (33.8) |
| Inpatient Rehabilitation Hospital [Member]                                          |           |           |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |   |   |
| Net operating revenues                                                              | 752.6          | 645.3          | 1,501.8 | 1,275.6 |
| Provision for Doubtful Accounts                                                     | (14.5)         | (10.2)         | (30.1) | (21.2) |
| Net operating revenues less provision for doubtful accounts                         | 738.1          | 635.1          | 1,471.7 | 1,254.4 |
| **Costs and Expenses [Abstract]**                                                   |           |           |   |   |
| Salaries and benefits                                                               | 366.1          | 317.6          | 736.0 | 624.0 |
| Other operating expenses                                                            | 106.8          | 93.5           | 211.6 | 188.7 |
| Supplies                                                                            | 31.8           | 29.9           | 64.2 | 59.7 |
| Occupancy costs                                                                     | 15.4           | 10.7           | 31.0 | 21.1 |
| Total segment level operating expenses                                              | 520.1          | 451.7          | 1,042.8 | 893.5 |
| Other income                                                                        | (0.7)          | (0.4)          | (1.3) | (0.9) |
| Equity in net income of nonconsolidated affiliates                                  | (2.2)          | (2.3)          | (4.4) | (3.9) |
| Noncontrolling interest                                                             | 16.8           | 15.6           | 33.6 | 30.8 |
| Segment Adjusted EBITDA                                                             | 204.1          | 170.5          | 401.0 | 334.9 |
| Capital Expenditures                                                                | 47.4           | 33.1           | 86.1 | 59.4 |
| Home Health and Hospice [Member]                                                    |           |           |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |   |   |
| Net operating revenues                                                              | 168.1          | 119.1          | 328.7 | 229.4 |
| Provision for Doubtful Accounts                                                     | (0.9)          | (0.7)          | (1.8) | (1.3) |
| Net operating revenues less provision for doubtful accounts                         | 167.2          | 118.4          | 326.9 | 228.1 |
| **Costs and Expenses [Abstract]**                                                   |           |           |   |   |
| Cost of services sold (excluding depreciation and amortization)                     | 81.6           | 56.7           | 160.0 | 110.1 |
| Support and overhead costs                                                          | 58.0           | 41.0           | 115.0 | 79.1 |
| Total segment level operating expenses                                              | 139.6          | 97.7           | 275.0 | 189.2 |
| Other income                                                                        | 0.0            | 0.0            | 0.0 | 0.0 |
| Equity in net income of nonconsolidated affiliates                                  | (0.2)          | 0.0            | (0.4) | 0.0 |
| Noncontrolling interest                                                             | 1.8            | 1.7            | 3.7 | 3.0 |
| Segment Adjusted EBITDA                                                             | 26.0           | 19.0           | 48.6 | 35.9 |
| Capital Expenditures                                                                | $ 1.9          | $ 1.9          | $ 2.4 | $ 2.2 |

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The amount of net revenues for a healthcare company resulting from a reduction in net operating revenues by the amount recorded for the provision for doubtful accounts (bad debt expense).
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Amounts paid for rent associated with leased hospitals, including common area maintenance and similar charges.
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The aggregate cost of services rendered during the reporting period, excluding depreciation, depletion and amortization.
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Total costs of sales and operating expenses for the period.
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Amount of revenues recognized by the entity from providing services to in-patients, outpatients, residents in facilities owned or operated by the entity, from insurance premiums, or from goods provided or services performed.
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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.
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The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.
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Amount of Net Income (Loss) attributable to noncontrolling interest.
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The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.
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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.
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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.
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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.
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