| **Investments in and Advances to Nonconsolidated Affiliates - Textual (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended                              |                                                                                   |                                          |
|----------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------|-----------------------------------------------------------------------------------|------------------------------------------|
||
| **Investments in and Advances to Nonconsolidated Affiliates (Textual) [Abstract]**                                               |                                         |                                                                              |                                     |
| Number of Partially-Owned Subsidiaries                                                                                           |                                         | 9hls_NumberOfPartiallyOwnedSubsidiariesNonconsolidated                            |                                     |
| Number of General or Limited Partnerships, Limited Liability Companies, or Joint Ventures                                        |                                         | 8hls_NumberOfGeneralOrLimitedPartnershipsLimitedLiabilityCompaniesOrJointVentures |                                     |
| Affiliates Ownership Percentage                                                                                                  |                                         |                                                                              | 100.00%hls_AffiliatesOwnershipPercentage |
| Goodwill, Period Increase                                                                                                        | $ 15.6us-gaap_GoodwillPeriodIncreaseDecrease |                                                                              |                                     |
| Minimum [Member]                                                                                                                 |                                         |                                                                              |                                     |
| **Investments in and Advances to Nonconsolidated Affiliates (Textual) [Abstract]**                                               |                                         |                                                                              |                                     |
| Affiliates Ownership Percentage                                                                                                  |                                         | 1.00%hls_AffiliatesOwnershipPercentage/ us-gaap_RangeAxis= us-gaap_MinimumMember  |                                     |
| Maximum [Member]                                                                                                                 |                                         |                                                                              |                                     |
| **Investments in and Advances to Nonconsolidated Affiliates (Textual) [Abstract]**                                               |                                         |                                                                              |                                     |
| Affiliates Ownership Percentage                                                                                                  |                                         | 51.00%hls_AffiliatesOwnershipPercentage/ us-gaap_RangeAxis= us-gaap_MaximumMember |                                     |

| X                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The percentage of ownership by the Company in the investee accounted for under the equity or cost methods of accounting.
+ References
No definition available.
+ Details**Name:**hls_AffiliatesOwnershipPercentage**Namespace Prefix:**hls_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**hls_InvestmentsInAndAdvancesToNonconsolidatedAffiliatesTextualAbstract**Namespace Prefix:**hls_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of general or limited partnerships, limited liability companies, or joint ventures of which the Company has investments.
+ References
No definition available.
+ Details**Name:**hls_NumberOfGeneralOrLimitedPartnershipsLimitedLiabilityCompaniesOrJointVentures**Namespace Prefix:**hls_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of partially owned subsidiaries in which the Company has investments but are not consolidated.
+ References
No definition available.
+ Details**Name:**hls_NumberOfPartiallyOwnedSubsidiariesNonconsolidated**Namespace Prefix:**hls_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267
+ Details**Name:**us-gaap_GoodwillPeriodIncreaseDecrease**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_RangeAxis=us-gaap_MaximumMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_RangeAxis=us-gaap_MinimumMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |