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GUARANTEES AND CONTINGENCIES (Detail) $ in Millions | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2017 USD ($) | May 01, 2014 matter | Jan. 06, 2012 provider
Loss Contingencies [Line Items] |  |  |
Number of medical providers questioned (one or more) | provider |  |  | 1
Number of matters related to a Notice of Non-Intervention | matter |  | 1 |
TRICARE Contract |  |  |
Loss Contingencies [Line Items] |  |  |
Contract term, years | 5 years |  |
Total Medicare |  |  |
Loss Contingencies [Line Items] |  |  |
Percentage of premiums and services revenue | 78.00% |  |
Military services |  |  |
Loss Contingencies [Line Items] |  |  |
Percentage of premiums and services revenue | 1.00% |  |
Medicaid |  |  |
Loss Contingencies [Line Items] |  |  |
Percentage of premiums and services revenue | 5.00% |  |
Penn Treaty Insolvency | Insurance-related Assessments |  |  |
Loss Contingencies [Line Items] |  |  |
Loss contingency, estimate of possible loss | $ | $ 54 |  |

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