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Loss And Loss Adjustment Expense Reserves Incurred and Paid Claims Development with IBNR and Claim Counts (Details) $ in Millions | Dec. 31, 2017 USD ($) claim | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
--- | --- | --- | --- | --- | ---
Claims Development [Line Items] |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | $ 10,029.8 | $ 8,800.0 |  |  |
Commercial Lines - Physical Damage | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,560.9 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,509.6 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 0.4 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 51.7 | 46.6 |  |  |
Commercial Lines - Liability | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 5,157.5 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,158.6 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 28.5 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 2,027.4 | 1,675.3 |  |  |
Property | Property Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,247.8 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,009.2 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 7.2 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 245.8 | 224.7 |  |  |
2013 | Commercial Lines - Physical Damage | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 254.2 | 253.7 | $ 254.5 | $ 254.2 | $ 256.2
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 62,673 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 253.8 | 253.7 | 253.9 | 253.1 | 239.4
2013 | Commercial Lines - Liability | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 840.8 | 865.0 | 865.4 | 864.6 | 864.2
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 78,075 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 802.6 | 752.5 | 659.1 | 509.4 | 233.3
2013 | Property | Property Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 253.9 | 254.1 | 254.3 | 283.3 | 307.3
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 2.5 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 30,600 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 250.5 | 249.5 | 244.9 | 234.2 | 185.1
2014 | Commercial Lines - Physical Damage | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 238.0 | 238.6 | 239.7 | 240.3 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (0.5) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 59,622 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 237.9 | 237.7 | 238.3 | 224.6 |
2014 | Commercial Lines - Liability | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 823.0 | 820.3 | 795.4 | 822.5 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 15.9 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 74,724 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 715.3 | 610.0 | 438.7 | 234.0 |
2014 | Property | Property Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 376.3 | 379.7 | 389.1 | 415.5 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 3.6 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 40,984 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 370.3 | 365.9 | 351.5 | 269.2 |
2015 | Commercial Lines - Physical Damage | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 273.5 | 274.1 | 274.4 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (0.1) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 62,593 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 272.0 | 271.9 | 248.5 |  |
2015 | Commercial Lines - Liability | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 914.8 | 911.1 | 897.6 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 23.7 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 77,807 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 675.0 | 501.5 | 238.4 |  |
2015 | Property | Property Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 403.6 | 416.5 | 460.0 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 11.5 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 41,957 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 383.5 | 372.8 | 280.3 |  |
2016 | Commercial Lines - Physical Damage | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 379.8 | 379.6 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (0.9) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 74,217 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 376.9 | 336.7 |  |  |
2016 | Commercial Lines - Liability | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,204.8 | 1,185.8 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 63.1 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 92,196 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 639.9 | 298.6 |  |  |
2016 | Property | Property Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 541.2 | 568.6 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 24.8 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 53,323 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 498.2 | 415.2 |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Commercial Lines - Physical Damage | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 415.4 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (5.7) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 77,767 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 369.0 |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Commercial Lines - Liability | Commercial Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,374.1 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 219.2 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 94,992 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 325.8 |  |  |  |
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Property | Property Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 672.8 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 99.7 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 64,487 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 506.7 |  |  |  |
Agency Channel | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 19,542.2 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 15,641.9 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 55.2 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 3,955.5 | 3,555.9 |  |  |
Agency Channel | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 11,257.9 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 11,232.6 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 0.9 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 26.2 | 30.1 |  |  |
Agency Channel | 2013 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,484.2 | 3,528.0 | 3,518.2 | 3,520.9 | 3,506.0
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 696,624 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,437.6 | 3,362.9 | 3,173.1 | 2,794.1 | 1,684.0
Agency Channel | 2013 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,001.1 | 1,999.4 | 2,000.1 | 2,001.4 | 2,014.0
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,347,920 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,000.8 | 2,001.3 | 2,002.0 | 2,003.9 | 1,952.7
Agency Channel | 2014 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,654.4 | 3,633.2 | 3,627.7 | 3,702.1 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 50.9 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 701,787 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,482.3 | 3,284.5 | 2,868.1 | 1,809.0 |
Agency Channel | 2014 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,088.0 | 2,089.9 | 2,090.3 | 2,107.5 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (3.3) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,374,666 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,090.7 | 2,090.6 | 2,091.6 | 2,078.8 |
Agency Channel | 2015 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,798.8 | 3,773.8 | 3,774.9 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 59.2 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 704,990 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,416.5 | 2,976.0 | 1,793.1 |  |
Agency Channel | 2015 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,134.4 | 2,137.2 | 2,136.8 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (2.6) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,336,268 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,134.4 | 2,138.1 | 2,106.2 |  |
Agency Channel | 2016 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 4,130.0 | 4,082.9 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 158.7 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 738,563 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,231.5 | 1,941.6 |  |  |
Agency Channel | 2016 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,398.9 | 2,423.4 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (12.1) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,398,371 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,406.9 | 2,391.0 |  |  |
Agency Channel | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 4,474.8 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 679.6 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 765,553 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,074.0 |  |  |  |
Agency Channel | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,635.5 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (101.8) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,496,298 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,599.8 |  |  |  |
Direct Channel | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 16,934.1 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 13,282.5 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 33.5 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 3,685.1 | 3,219.1 |  |  |
Direct Channel | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 10,813.7 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 10,819.4 |  |  |  |
All outstanding liabilities before 2013, net of reinsurance1 | 0.1 |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | (5.6) | 11.2 |  |  |
Direct Channel | 2013 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,612.9 | 2,649.8 | 2,615.8 | 2,621.8 | 2,619.4
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 550,166 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,577.8 | 2,521.3 | 2,375.5 | 2,085.1 | 1,252.0
Direct Channel | 2013 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,635.0 | 1,633.4 | 1,634.6 | 1,635.6 | 1,653.7
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,367,341 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 1,635.0 | 1,635.3 | 1,636.2 | 1,638.2 | $ 1,612.9
Direct Channel | 2014 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,913.6 | 2,898.1 | 2,887.4 | 2,946.8 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 38.2 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 592,185 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,780.0 | 2,624.2 | 2,278.0 | 1,413.0 |
Direct Channel | 2014 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 1,859.2 | 1,861.7 | 1,862.2 | 1,889.3 |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (3.2) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,471,016 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 1,861.8 | 1,862.7 | 1,864.1 | $ 1,874.6 |
Direct Channel | 2015 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,354.2 | 3,328.3 | 3,330.5 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 48.6 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 659,102 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 3,021.0 | 2,615.0 | 1,545.2 |  |
Direct Channel | 2015 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,093.5 | 2,097.7 | 2,110.7 |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (3.0) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,539,790 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,094.7 | 2,100.1 | $ 2,094.7 |  |
Direct Channel | 2016 | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 3,843.9 | 3,819.0 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 143.0 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 733,195 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,991.1 | 1,780.6 |  |  |
Direct Channel | 2016 | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,475.4 | 2,521.0 |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (14.3) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,675,405 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,485.8 | $ 2,505.0 |  |  |
Direct Channel | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Personal Lines - Liability | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 4,209.5 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ 598.6 |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 761,280 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 1,912.6 |  |  |  |
Direct Channel | Short-duration Insurance Contracts, Accident Year 2017 [Member] | Personal Lines - Physical Damage | Personal Lines Segment |  |  |  |  |
Claims Development [Line Items] |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | 2,750.6 |  |  |  |
Total of IBNR Liabilities Plus Expected Development on Reported Claims | $ (145.3) |  |  |  |
Cumulative Number of Incurred Claim Counts | claim | 1,779,665 |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance | $ 2,742.1 |  |  |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount, after reinsurance, of paid claims and allocated claim adjustment expense used in claims development for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671311-158438 + Details
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- Definition Undiscounted amount, after reinsurance, of incurred-but-not-reported (IBNR) liabilities plus expected development on reported claims, for claims and allocated claim adjustment expense for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4D -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671317-158438 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4E -URI http://asc.fasb.org/extlink&oid=65670685&loc=SL65671321-158438 + Details
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