| **Redeemable Noncontrolling Interests**            | 12 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 (in millions): For the Year Ended December 31, 2014 2013 2012Balance at beginning of period$13.5 $7.2 $7.3Acquisition of Encompass64.5 — —Net income attributable to noncontrolling interests6.6 5.8 3.8Distributions(8.5) (4.9) (3.9)Contribution to joint venture4.3 7.1 —Change in fair value4.3 (1.7) —Balance at end of period$84.7 $13.5 $7.2The following table reconciles the net income attributable to nonredeemable Noncontrolling interests, as recorded in the shareholders’ equity section of the consolidated balance sheets, and the net income attributable to Redeemable noncontrolling interests, as recorded in the mezzanine section of the consolidated balance sheets, to the Net income attributable to noncontrolling interests presented on the consolidated statements of operations (in millions): For the Year Ended December 31, 2014 2013 2012Net income attributable to nonredeemable noncontrolling interests$53.1 $52.0 $47.1Net income attributable to redeemable noncontrolling interests6.6 5.8 3.8Net income attributable to noncontrolling interests$59.7 $57.8 $50.9See also Note 2,Business Combinations. |

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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 |