| **Summary of Significant Accounting Policies (Tables)**                  | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| **Accounting Policies [Abstract]**                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Concentration of Net Operating Revenues by Payor                         | We derived consolidated Net operating revenues from the following payor sources: For the Year Ended December 31, 2014 2013 2012Medicare74.1% 74.5% 73.4%Medicaid1.8% 1.2% 1.2%Workers' compensation1.2% 1.2% 1.5%Managed care and other discount plans, including Medicare Advantage18.6% 18.5% 19.3%Other third-party payors1.8% 1.8% 1.8%Patients1.0% 1.1% 1.3%Other income1.5% 1.7% 1.5%Total100.0% 100.0% 100.0%                                                    |
| Concentration of Net Patient Service Accounts Receivable by Payor Class  | The concentration of net patient service accounts receivable by payor class, as a percentage of total net patient service accounts receivable, is as follows: As of December 31, 2014 2013Medicare72.2% 67.4%Medicaid1.8% 2.0%Workers' compensation1.9% 2.6%Managed care and other discount plans, including Medicare Advantage18.5% 22.4%Other third-party payors3.8% 4.0%Patients1.8% 1.6%Total100.0% 100.0%                                                                                                            |
| Useful Lives of Property and Equipment                                   | Useful lives are generally as follows: YearsBuildings10 to 30Leasehold improvements2 to 15Vehicles5Furniture, fixtures, and equipment3 to 10Assets under capital lease obligations: Real estate15 to 20Vehicles3 to 4Equipment3 to 5                                                                                                                                                                                                                                                                                                                              |
| Estimated Useful Lives and Amortization Basis of Other Intangible Assets | 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 agreements2 to 18 years using straight-line basisTrade names:Encompassindefinite-lived assetAll other10 to 20 years using straight-line basisInternal-use software3 to 7 years using straight-line basisMarket access assets20 years using accelerated basis |

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| - Definition
Tabular disclosure of the concentration of net operating revenues by payor class as a percentage of total net operating revenues.
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No definition available.
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| - Definition
Tabular disclosure of the concentration of net patient service accounts receivable by payor class as a percentage of total net patient service accounts receivable.
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No definition available.
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| - Definition
Tabular disclosure of estimated useful lives and amortization basis of the Company's finite-lived intangible assets by major class.
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No definition available.
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| - Definition
Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5
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