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Litigation and Contingencies (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract] |  |
Average paid claim reduction due to curtailments (as a percent) | 3.90% | 5.80%
Probable loss contingency accrual | $ 23.5 |
Maximum exposure associated with other discussions and legal proceedings | $ 266.2 |

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- Definition Amount of loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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