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Reinsurance (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |
Percentage of ceded earned premiums to gross earned premiums | 37.00% | 41.00% | 38.00% | 40.00%
Percentage of assumed earned premiums to net earned premiums | 27.00% | 29.00% | 27.00% | 27.00%
Program services and other [Member] |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |
Reinsurance recoverables | $ 394.5 | $ 338.8 | $ 702.5 | $ 703.8

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- Definition Percentage of assumed premium earned to premium earned after effects of reinsurance, as disclosed in supplementary reinsurance information. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column F)) -URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915 + Details
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- Definition Amount of reduction of provision for policy benefits and costs incurred for policies ceded. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387 + Details
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