| **Basis of Presentation - Table 1 (Details) - Net operating revenues [Member] - Payor Source [Member]**    | 3 Months Ended | 9 Months Ended |
|------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 100.00%        | 100.00%        | 100.00% | 100.00% |
| Inpatient Rehabilitation Segment [Member]                                                                  |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 100.00%        | 100.00%        | 100.00% | 100.00% |
| Home Health and Hospice Segment [Member]                                                                   |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 100.00%        | 100.00%        | 100.00% | 100.00% |
| Other Income Source [Member]                                                                               |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 1.10%          | 1.30%          | 1.20% | 1.30% |
| Other Income Source [Member] | Inpatient Rehabilitation Segment [Member]                                   |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 1.30%          | 1.60%          | 1.40% | 1.50% |
| Other Income Source [Member] | Home Health and Hospice Segment [Member]                                    |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 0.10%          | 0.00%          | 0.10% | 0.00% |
| Third-Party Payor [Member] | Medicare [Member]                                                             |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 74.80%         | 75.10%         | 75.00% | 74.80% |
| Third-Party Payor [Member] | Medicare [Member] | Inpatient Rehabilitation Segment [Member]                 |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 73.30%         | 73.20%         | 73.30% | 73.00% |
| Third-Party Payor [Member] | Medicare [Member] | Home Health and Hospice Segment [Member]                  |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 81.80%         | 84.70%         | 82.40% | 84.10% |
| Third-Party Payor [Member] | Medicare Advantage [Member]                                                   |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 7.90%          | 7.50%          | 7.90% | 7.80% |
| Third-Party Payor [Member] | Medicare Advantage [Member] | Inpatient Rehabilitation Segment [Member]       |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 7.60%          | 7.70%          | 7.70% | 7.90% |
| Third-Party Payor [Member] | Medicare Advantage [Member] | Home Health and Hospice Segment [Member]        |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 8.80%          | 6.70%          | 8.90% | 7.10% |
| Third-Party Payor [Member] | Managed Care [Member]                                                         |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 10.10%         | 9.90%          | 9.90% | 10.00% |
| Third-Party Payor [Member] | Managed Care [Member] | Inpatient Rehabilitation Segment [Member]             |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 11.40%         | 11.20%         | 11.30% | 11.30% |
| Third-Party Payor [Member] | Managed Care [Member] | Home Health and Hospice Segment [Member]              |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 4.50%          | 2.90%          | 3.70% | 2.90% |
| Third-Party Payor [Member] | Medicaid [Member]                                                             |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 3.30%          | 3.40%          | 3.30% | 3.00% |
| Third-Party Payor [Member] | Medicaid [Member] | Inpatient Rehabilitation Segment [Member]                 |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 3.00%          | 3.00%          | 3.00% | 2.60% |
| Third-Party Payor [Member] | Medicaid [Member] | Home Health and Hospice Segment [Member]                  |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 4.70%          | 5.70%          | 4.80% | 5.70% |
| Third-Party Payor [Member] | Other Third-party Payors [Member]                                             |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 1.50%          | 1.50%          | 1.40% | 1.60% |
| Third-Party Payor [Member] | Other Third-party Payors [Member] | Inpatient Rehabilitation Segment [Member] |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 1.80%          | 1.70%          | 1.70% | 1.90% |
| Third-Party Payor [Member] | Other Third-party Payors [Member] | Home Health and Hospice Segment [Member]  |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 0.00%          | 0.00%          | 0.00% | 0.10% |
| Third-Party Payor [Member] | Workers' Compensation [Member]                                                |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 0.80%          | 0.80%          | 0.80% | 0.90% |
| Third-Party Payor [Member] | Workers' Compensation [Member] | Inpatient Rehabilitation Segment [Member]    |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 1.00%          | 1.00%          | 1.00% | 1.10% |
| Self-Pay [Member] | Patients [Member]                                                                      |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 0.50%          | 0.50%          | 0.50% | 0.60% |
| Self-Pay [Member] | Patients [Member] | Inpatient Rehabilitation Segment [Member]                          |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 0.60%          | 0.60%          | 0.60% | 0.70% |
| Self-Pay [Member] | Patients [Member] | Home Health and Hospice Segment [Member]                           |           |           |   |   |
| **Concentration Risk [Line Items]**                                                                        |           |           |   |   |
| Net operating revenues by payor source (percent)                                                           | 0.10%          | 0.00%          | 0.10% | 0.10% |

| X                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ References
No definition available.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.
+ References
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