| **Segment Reporting Segment Reporting - Table 3 (Details) - USD ($) $ in Millions**                           | 3 Months Ended | 6 Months Ended |
|---------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]** |           |           |   |   |   |
| General and administrative expenses                                                                           | $ (34.4)       |           | $ (32.1) | $ (66.3) | $ (66.7) |
| Depreciation and amortization                                                                                 | (42.9)         |           | (32.7) | (85.3) | (64.6) |
| (Loss) gain on disposal or impairment of assets                                                               | (0.2)          |           | (0.8) | (0.4) | 0.7 |
| Government, class action, and related settlements                                                             | 0.0            |           | 0.0 | 0.0 | (8.0) |
| Professional fees - accounting, tax, and legal                                                                | (1.7)          |           | (0.1) | (1.9) | (2.3) |
| Loss on early extinguishment of debt                                                                          | (2.4)          | $ (2.4)        | (18.8) | (4.8) | (20.0) |
| Interest expense and amortization of debt discounts and fees                                                  | (43.4)         |           | (30.9) | (88.0) | (62.7) |
| Net income attributable to noncontrolling interests                                                           | 18.6           |           | 17.3 | 37.3 | 33.8 |
| Gain related to SCA equity interest                                                                           | 0.0            |           | 2.6 | 0.0 | 2.6 |
| Income from continuing operations before income tax expense                                                   | 123.7          |           | 94.0 | 240.2 | 183.6 |
| Inpatient Rehabilitation Hospital and Home Health and Hospice [Member]                                        |           |           |   |   |   |
| **Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]** |           |           |   |   |   |
| Total segment Adjusted EBITDA                                                                                 | $ 230.1        |           | $ 189.5 | $ 449.6 | $ 370.8 |

| X                                                                                                                                                                                                                                                                                                                          |
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Adjusted earnings before interest, taxes, depreciation, and amortization as defined in the Company's credit agreement.
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| - Definition
Net gain or loss incurred by the entity for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, and settlements that resulted from or were related to our prior reporting and restatement issues.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| - Definition
The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.  In addition, the amount of increase (decrease) in the fair value of derivatives recognized in the income statement.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| - Definition
Fees charged for services from professionals such as lawyers, accountants, and other consultants for assistance with various projects that resulted from or were related to our prior reporting and restatement issues.
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| - Definition
The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.
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| - Definition
Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.
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| - Definition
Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.
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| - Definition
The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.
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| - Definition
This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.
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| - Definition
Interest and debt related expenses associated with nonoperating financing activities of the entity.
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| - Definition
Amount of Net Income (Loss) attributable to noncontrolling interest.
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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