v3.8.0.1

Acquisitions and Noncontrolling Interest - Non Controlling Interest (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Arkansas Total Care |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 74.00% | 0.00% | 0.00%
Celtic Insurance Company |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 100.00% | 100.00% | 75.00%
Cenpatico Integrated Care |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 80.00% | 80.00% | 80.00%
Centurion |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 51.00% | 51.00% | 51.00%
Foundation Care |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 80.00% | 0.00% | 0.00%
Home State Health Plan |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 95.00% | 95.00% | 95.00%
The Practice (Group) Limited (TPG) |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 75.00% | 75.00% | 49.00%
Acquisition consideration |  | $ 8 |
U.S. Medical Management |  |  |
Noncontrolling Interest [Line Items] |  |  |
Ownership percentage by parent | 100.00% | 68.00% | 68.00%
Foundation Care |  |  |
Noncontrolling Interest [Line Items] |  |  |
Acquisition consideration | $ 59 |  |
U.S. Medical Management |  |  |
Noncontrolling Interest [Line Items] |  |  |
Acquisition consideration | $ 86 |  |

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