| **Redeemable Noncontrolling Interests**            | 9 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 nine months ended September 30, 2014 and 2013 (in millions): Nine Months Ended September 30, 2014 2013Balance at beginning of period$13.5 $7.2Net income attributable to noncontrolling interests5.4 4.1Distributions declared(6.7) (3.6)Contribution to joint venture— 6.2Balance at end of period$12.2 $13.9The 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 nine months ended September 30, 2014 and 2013 (in millions): Three Months Ended September 30, Nine Months Ended September 30,  2014 2013 2014 2013Net income attributable to nonredeemable noncontrolling interests$12.9 $12.6 $38.9 $38.4Net income attributable to redeemable noncontrolling interests1.8 1.5 5.4 4.1Net income attributable to noncontrolling interests$14.7 $14.1 $44.3 $42.5 |

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