XML 124 R87.htm IDEA: XBRL DOCUMENT v3.8.0.1
Reinsurance Prepaid Reinsurance Premiums and Reinsurance Recoverables (Details) - USD ($)
$ in Millions
Dec. 31, 2017
Dec. 31, 2016
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 203.3 $ 170.5
Percentage Of Total Prepaid Reinsurance Premiums 100.00% 100.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 2,273.4 $ 1,884.8
Percentage Of Total Reinsurance Recoverables 100.00% 100.00%
State Reinsurance Plans [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 179.9 $ 153.4
Percentage Of Total Prepaid Reinsurance Premiums 88.00% 90.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 2,060.7 $ 1,772.3
Percentage Of Total Reinsurance Recoverables 91.00% 94.00%
State Reinsurance Plans [Member] | Michigan Catastrophic Claims Association [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 44.3 $ 36.5
Percentage Of Total Prepaid Reinsurance Premiums 22.00% 21.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 1,611.5 $ 1,452.7
Percentage Of Total Reinsurance Recoverables 71.00% 77.00%
State Reinsurance Plans [Member] | Commercial Auto Insurance Procedures Plans [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 50.0 $ 40.2
Percentage Of Total Prepaid Reinsurance Premiums 25.00% 24.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 218.0 $ 170.6
Percentage Of Total Reinsurance Recoverables 10.00% 9.00%
State Reinsurance Plans [Member] | North Carolina Reinsurance Facility [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 31.5 $ 27.5
Percentage Of Total Prepaid Reinsurance Premiums 15.00% 16.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 74.2 $ 67.0
Percentage Of Total Reinsurance Recoverables 3.00% 4.00%
State Reinsurance Plans [Member] | other reinsurance program [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 0.3 $ 0.1
Percentage Of Total Prepaid Reinsurance Premiums 0.00% 0.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 8.2 $ 3.5
Percentage Of Total Reinsurance Recoverables 0.00% 0.00%
Federal Reinsurance Plans [Member] | National Flood Insurance Program [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 53.8 $ 49.1
Percentage Of Total Prepaid Reinsurance Premiums 26.00% 29.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 148.8 $ 78.5
Percentage Of Total Reinsurance Recoverables 7.00% 4.00%
Non State Reinsurance Plans [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 23.4 $ 17.1
Percentage Of Total Prepaid Reinsurance Premiums 12.00% 10.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 212.7 $ 112.5
Percentage Of Total Reinsurance Recoverables 9.00% 6.00%
Property reinsurance program [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 9.1 $ 3.2
Percentage Of Total Prepaid Reinsurance Premiums 5.00% 2.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 138.6 $ 62.9
Percentage Of Total Reinsurance Recoverables 6.00% 3.00%
other reinsurance program [Member]    
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]    
Prepaid reinsurance premiums $ 14.3 $ 13.9
Percentage Of Total Prepaid Reinsurance Premiums 7.00% 8.00%
Reinsurance Recoverables, Including Reinsurance Premium Paid $ 74.1 $ 49.6
Percentage Of Total Reinsurance Recoverables 3.00% 3.00%