| **Redeemable Noncontrolling Interests**            | 3 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 three months ended March 31, 2015 and 2014 (in millions): Three Months Ended March 31, 2015 2014Balance at beginning of period$84.7 $13.5Net income attributable to noncontrolling interests2.9 2.0Distributions declared(1.7) (2.5)Change in fair value(1.2) —Balance at end of period$84.7 $13.0The 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 months ended March 31, 2015 and 2014 (in millions): Three Months Ended March 31,  2015 2014Net income attributable to nonredeemable noncontrolling interests$13.6 $12.8Net income attributable to redeemable noncontrolling interests2.9 2.0Net income attributable to noncontrolling interests$16.5 $14.8 |

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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 |