| **Goodwill and Other Intangible Assets (Tables)**                    | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|----------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Goodwill and Intangible Assets Disclosure [Abstract]**             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Schedule of Changes in the Carrying Amount of Goodwill               | The following table shows changes in the carrying amount of Goodwill for the years ended December 31, 2016, 2015, and 2014 (in millions): Inpatient Rehabilitation Home Health and Hospice ConsolidatedGoodwill as of December 31, 2013$456.9 $— $456.9Acquisitions0.6 592.5 593.1Consolidation of joint venture formerly accounted for under the equity method of accounting34.0 — 34.0Goodwill as of December 31, 2014491.5 592.5 1,084.0Acquisitions641.6 164.5 806.1Goodwill as of December 31, 20151,133.1 757.0 1,890.1Acquisitions8.9 42.5 51.4Divestiture of pediatric home health services— (14.3) (14.3)Goodwill as of December 31, 2016$1,142.0 $785.2 $1,927.2                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Schedule of Intangible Assets by Major Class                         | The range of estimated useful lives and the amortization basis for our intangible assets, excluding goodwill, are generally as follows: Estimated Useful Lifeand Amortization BasisCertificates of need10 to 30 years using straight-line basisLicenses10 to 20 years using straight-line basisNoncompete agreements1 to 18 years using straight-line basisTrade names: Encompassindefinite-lived assetAll other1 to 20 years using straight-line basisInternal-use software3 to 7 years using straight-line basisMarket access assets20 years using accelerated basisThe following table provides information regarding our other intangible assets (in millions): Gross Carrying Amount Accumulated Amortization NetCertificates of need:     2016$98.6 $(12.9) $85.7201593.9 (6.9) 87.0Licenses:     2016$142.0 $(62.1) $79.92015138.9 (53.7) 85.2Noncompete agreements:     2016$62.2 $(47.3) $14.9201558.0 (37.0) 21.0Trade name - Encompass:     2016$135.2 $— $135.22015135.2 — 135.2Trade names - all other:     2016$34.6 $(13.9) $20.7201532.9 (11.5) 21.4Internal-use software:     2016$181.4 $(110.2) $71.22015155.7 (90.5) 65.2Market access assets:     2016$13.2 $(9.5) $3.7201513.2 (8.8) 4.4Total intangible assets:     2016$667.2 $(255.9) $411.32015627.8 (208.4) 419.4 |
| Schedule of Amortization Expense, Intangible Assets                  | Amortization expense for other intangible assets is as follows (in millions): For the Year Ended December 31, 2016 2015 2014Amortization expense$48.5 $36.0 $20.3                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Schedule of Future Estimated Amortization Expense, Intangible Assets | Total estimated amortization expense for our other intangible assets for the next five years is as follows (in millions):Year Ending December 31,Estimated Amortization Expense2017$45.6201836.2201931.5202026.6202122.9                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |

| X                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tabular disclosure of amortization expense of assets, excluding financial assets, that lack physical substance, having a limited useful life.
+ References
No definition available.
+ Details**Name:**us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
+ Details**Name:**us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tabular disclosure of assets, excluding financial assets and goodwill, lacking physical substance with a finite life, by either major class or business segment.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275
+ Details**Name:**us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.
+ 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=d3e13816-109267Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267
+ Details**Name:**us-gaap_ScheduleOfGoodwillTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tabular disclosure of the amount of amortization expense expected to be recorded in succeeding fiscal years for finite-lived intangible assets.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275
+ Details**Name:**us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |