| **Redeemable Noncontrolling Interests**            | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| **Redeemable Noncontrolling Interests [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Redeemable Noncontolling Interests                 | Redeemable Noncontrolling InterestsThe following is a summary of the activity related to our Redeemable noncontrolling interests during the six months ended June 30, 2016 and 2015 (in millions): Six Months Ended June 30, 2016 2015Balance at beginning of period$121.1 $84.7Net income attributable to noncontrolling interests7.5 6.4Distributions declared(4.3) (4.0)Change in fair value(4.3) 11.4Balance at end of period$120.0 $98.5The following table reconciles the net income attributable to nonredeemable Noncontrolling interests, as recorded in the shareholders’ equity section of the condensed consolidated balance sheets, and the net income attributable to Redeemable noncontrolling interests, as recorded in the mezzanine section of the condensed consolidated balance sheets, to the Net income attributable to noncontrolling interests presented in the condensed consolidated statements of operations for the three and six months ended June 30, 2016 and 2015 (in millions): Three Months Ended June 30,  Six Months Ended June 30,  2016 2015 2016 2015Net income attributable to nonredeemable noncontrolling interests$15.0 $13.8 $29.8 $27.4Net income attributable to redeemable noncontrolling interests3.6 3.5 7.5 6.4Net income attributable to noncontrolling interests$18.6 $17.3 $37.3 $33.8 |

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| - Definition
The entire disclosure for redeemable noncontrolling interest in consolidated subsidiaries.
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No definition available.
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| - Definition
Redeemable Noncontrolling Interests [Abstract]
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No definition available.
+ Details**Name:**hls_RedeemableNoncontrollingInterestsAbstract**Namespace Prefix:**hls_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |