| **Variable Interest Entities Variable Interest Entities** | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| **Variable Interest Entities [Abstract]**                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Variable Interest Entity Disclosure [Text Block]          | Variable Interest EntitiesAs of June 30, 2016, we consolidated ten limited partnership-like entities that are VIEs and of which we are the primary beneficiary. All ten of these entities were also consolidated as of December 31, 2015. Our ownership percentages in these entities range from 6.8% to 99.5%. Through partnership and management agreements with or governing each of these entities, we manage all of these entities and handle all day-to-day operating decisions. Accordingly, we have the decision making power over the activities that most significantly impact the economic performance of our VIEs and an obligation to absorb losses or receive benefits from the VIE that could potentially be significant to the VIE. These decisions and significant activities include, but are not limited to, marketing efforts, oversight of patient admissions, medical training, nurse and therapist scheduling, provision of healthcare services, billing, collections and creation and maintenance of medical records. The terms of the agreements governing each of our VIEs prohibit us from using the assets of each VIE to satisfy the obligations of other entities.The carrying amounts and classifications of the consolidated VIEs’ assets and liabilities, which are included in our consolidated balance sheet, are as follows (in millions): June 30, 2016Assets Current assets: Cash and cash equivalents$1.5Accounts receivable, net of allowance for doubtful accounts31.4Other current assets6.7Total current assets39.6Property and equipment, net132.6Goodwill73.5Intangible assets, net8.6Other long-term assets1.0Total assets$255.3Liabilities Current liabilities: Current portion of long-term debt$1.4Accounts payable8.5Accrued expenses and other current liabilities14.1Total current liabilities24.0Long-term debt, net of current portion30.6Total liabilities$54.6 |

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| - Definition
Variable Interest Entities [Abstract]
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No definition available.
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| - Definition
The entire disclosure for a variable interest entity (VIE), including but not limited to, judgments and assumptions in determining whether to consolidate and in identifying the primary beneficiary, gain (loss) recognized on the initial consolidation of the VIE, terms of arrangements, amounts and classification of the VIE's assets and liabilities, and the entity's maximum exposure to loss.
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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -URI http://asc.fasb.org/extlink&oid=52262685&loc=SL6759159-111685Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5728-111685Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5710-111685
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