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Litigation and Contingencies (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract] |  |
Average paid claim reduction due to curtailments (as a percent) | 5.50% | 5.50%
Maximum exposure associated with other discussions and legal proceedings | $ 291 |

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- Definition Average paid claim reduction due to curtailments. + References No definition available. + Details
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- Definition Estimated maximum exposure associated with other discussions and legal proceedings related to claims paying practices. + References No definition available. + Details
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