| **Segment Reporting - Table 5 (Details) - USD ($) $ in Millions**         | 3 Months Ended |
|---------------------------------------------------------------------------|----------------|
||
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | $ 974.8        | $ 909.8 |
| Inpatient Rehabilitation Segment [Member]                                 |           |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | 792.5          | 749.2 |
| Inpatient Rehabilitation Segment [Member] | Inpatient [Member]            |           |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | 766.2          | 719.4 |
| Inpatient Rehabilitation Segment [Member] | Outpatient and other [Member] |           |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | 26.3           | 29.8 |
| Home Health and Hospice Segment [Member]                                  |           |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | 182.3          | 160.6 |
| Home Health and Hospice Segment [Member] | Home health [Member]           |           |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | 165.3          | 150.9 |
| Home Health and Hospice Segment [Member] | Hospice [Member]               |           |   |
| **Segment Reporting, Revenue Reconciling Item [Line Items]**              |           |   |
| Net operating revenues                                                    | $ 17.0         | $ 9.7 |

| 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                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=hls_InpatientRehabilitationSegmentMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_SubsegmentsAxis=hls_InpatientMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_SubsegmentsAxis=hls_OutpatientandotherMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=hls_HomeHealthandHospiceSegmentMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_SubsegmentsAxis=hls_HomehealthMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_SubsegmentsAxis=hls_HospiceMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |