| **Segment Reporting - Table 5 (Details) - USD ($) $ in Millions**         | 3 Months Ended | 6 Months Ended |
|---------------------------------------------------------------------------|----------------|----------------|
||
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | $ 981.3        | $ 920.7        | $ 1,956.1 | $ 1,830.5 |
| Inpatient Rehabilitation Segment [Member]                                 |           |           |   |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | 790.0          | 752.6          | 1,582.5 | 1,501.8 |
| Inpatient Rehabilitation Segment [Member] | Inpatient [Member]            |           |           |   |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | 762.9          | 721.2          | 1,529.1 | 1,440.5 |
| Inpatient Rehabilitation Segment [Member] | Outpatient and other [Member] |           |           |   |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | 27.1           | 31.4           | 53.4 | 61.3 |
| Home Health and Hospice Segment [Member]                                  |           |           |   |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | 191.3          | 168.1          | 373.6 | 328.7 |
| Home Health and Hospice Segment [Member] | Home health [Member]           |           |           |   |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | 172.9          | 157.1          | 338.2 | 308.0 |
| Home Health and Hospice Segment [Member] | Hospice [Member]               |           |           |   |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |           |   |   |
| Net operating revenues                                                    | $ 18.4         | $ 11.0         | $ 35.4 | $ 20.7 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688
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| 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.
+ Details**Name:**us-gaap_SegmentReportingRevenueReconcilingItemLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=hls_HomeHealthandHospiceSegmentMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_SubsegmentsAxis=hls_HospiceMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |