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Unpaid Claims and Claim Expenses - Incurred and Paid Claims by Accident Year on a Net Basis (Details) $ in Millions | Dec. 31, 2021 USD ($) claim | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($) | Dec. 31, 2012 USD ($)
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Homeowners |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 1,270.0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,217.2 |  |  |  |  |  |  |  |  |
Outstanding prior to 2012 | 0.0 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 52.8 |  |  |  |  |  |  |  |  |
Homeowners | 2012 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 106.0 | $ 106.0 | $ 106.0 | $ 106.0 | $ 106.3 | $ 106.3 | $ 106.5 | $ 109.4 | $ 109.2 | $ 108.8
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 21,600,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 106.0 | 106.0 | 106.0 | 106.0 | 105.9 | 105.6 | 105.2 | 104.2 | 101.6 | 84.3
Homeowners | 2013 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 101.7 | 101.7 | 101.7 | 101.8 | 102.3 | 102.4 | 104.0 | 107.5 | 105.6 |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 19,200,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 101.7 | 101.7 | 101.7 | 101.7 | 101.5 | 101.0 | 99.4 | 96.6 | 76.9 |
Homeowners | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 106.4 | 106.4 | 106.6 | 106.6 | 106.8 | 109.1 | 113.5 | 111.6 |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 20,100,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 106.4 | 106.4 | 106.4 | 106.3 | 106.1 | 105.7 | 103.0 | 83.3 |  |
Homeowners | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 114.9 | 114.9 | 115.1 | 114.1 | 114.4 | 115.1 | 111.7 |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 18,700,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 114.7 | 114.9 | 114.6 | 113.3 | 111.9 | 109.3 | 90.7 |  |  |
Homeowners | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 117.9 | 117.9 | 117.9 | 117.0 | 118.6 | 115.9 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 19,900,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 117.8 | 117.7 | 117.5 | 115.1 | 113.2 | 95.8 |  |  |  |
Homeowners | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 130.8 | 130.7 | 132.7 | 129.8 | 126.3 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 19,900,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 130.5 | 130.0 | 129.8 | 128.5 | 106.8 |  |  |  |  |
Homeowners | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 158.1 | 158.9 | 157.4 | 166.8 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 21,100,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 157.4 | 157.0 | 152.4 | 130.5 |  |  |  |  |  |
Homeowners | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 132.1 | 129.9 | 130.4 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2.5 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 17,500,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 129.1 | 126.2 | 103.8 |  |  |  |  |  |  |
Homeowners | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 151.9 | 155.7 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 11.1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 19,600,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 138.7 | 106.8 |  |  |  |  |  |  |  |
Homeowners | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 150.2 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 22.6 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 15,500,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 114.9 |  |  |  |  |  |  |  |  |
Auto liability |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,656.3 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,486.3 |  |  |  |  |  |  |  |  |
Outstanding prior to 2012 | 1.5 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 171.5 |  |  |  |  |  |  |  |  |
Auto liability | 2012 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 145.8 | 145.9 | 145.5 | 145.6 | 145.8 | 147.6 | 149.3 | 150.3 | 153.8 | 156.4
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 18,600,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 145.3 | 145.3 | 145.2 | 145.1 | 144.6 | 142.9 | 138.6 | 127.2 | 109.6 | 61.3
Auto liability | 2013 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 147.7 | 148.3 | 148.1 | 148.0 | 148.1 | 150.7 | 150.7 | 152.9 | 153.9 |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 19,400,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 147.5 | 147.4 | 147.4 | 146.8 | 145.3 | 140.0 | 131.2 | 108.9 | 62.2 |
Auto liability | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 159.4 | 159.3 | 159.4 | 159.8 | 159.9 | 158.5 | 157.2 | 155.1 |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.2 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 20,300,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 158.8 | 158.6 | 157.6 | 155.8 | 149.1 | 139.5 | 117.5 | 61.3 |  |
Auto liability | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 178.9 | 179.2 | 178.7 | 178.3 | 177.0 | 172.6 | 165.5 |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.4 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 20,800,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 177.7 | 176.7 | 174.5 | 170.1 | 158.0 | 134.5 | 70.8 |  |  |
Auto liability | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 189.2 | 188.1 | 186.6 | 184.6 | 184.4 | 180.4 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 21,300,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 188.1 | 184.5 | 177.8 | 166.8 | 140.9 | 73.1 |  |  |  |
Auto liability | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 191.7 | 189.1 | 188.6 | 188.8 | 188.0 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 20,100,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 185.8 | 179.8 | 166.6 | 139.5 | 70.7 |  |  |  |  |
Auto liability | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 189.8 | 192.9 | 195.3 | 200.3 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 3.8 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 19,500,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 180.7 | 168.6 | 141.5 | 77.5 |  |  |  |  |  |
Auto liability | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 176.7 | 180.1 | 181.1 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 8.9 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 18,900,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 155.5 | 129.1 | 69.7 |  |  |  |  |  |  |
Auto liability | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 134.9 | 137.0 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 20.1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 13,100,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 94.0 | 51.5 |  |  |  |  |  |  |  |
Auto liability | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 142.2 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 55.3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 12,800,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 52.9 |  |  |  |  |  |  |  |  |
Auto physical damage |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 994.7 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 988.0 |  |  |  |  |  |  |  |  |
Outstanding prior to 2012 | 0.0 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 6.7 |  |  |  |  |  |  |  |  |
Auto physical damage | 2012 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 83.3 | 83.3 | 83.3 | 83.3 | 83.3 | 83.4 | 83.4 | 83.4 | 82.3 | 83.8
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 78,200,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 83.3 | 83.3 | 83.3 | 83.3 | 83.3 | 83.3 | 83.4 | 83.4 | 83.4 | $ 80.5
Auto physical damage | 2013 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 88.4 | 88.5 | 88.5 | 88.5 | 88.5 | 88.6 | 88.7 | 88.9 | 91.4 |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 80,900,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 88.4 | 88.4 | 88.5 | 88.5 | 88.5 | 88.5 | 88.6 | 88.7 | $ 85.1 |
Auto physical damage | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 95.2 | 95.2 | 95.2 | 95.2 | 95.2 | 95.4 | 95.6 | 95.6 |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 87,900,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 95.2 | 95.2 | 95.2 | 95.3 | 95.3 | 95.3 | 95.4 | $ 88.9 |  |
Auto physical damage | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 97.6 | 97.6 | 97.6 | 97.5 | 97.6 | 98.0 | 99.3 |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 87,500,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 97.6 | 97.6 | 97.6 | 97.6 | 97.7 | 97.9 | $ 92.1 |  |  |
Auto physical damage | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 109.5 | 109.6 | 109.6 | 109.3 | 109.5 | 112.4 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 93,200,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 109.6 | 109.6 | 109.6 | 109.5 | 109.7 | $ 106.5 |  |  |  |
Auto physical damage | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 110.5 | 110.6 | 110.5 | 111.8 | 115.5 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 91,300,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 110.6 | 110.6 | 110.7 | 110.8 | $ 105.2 |  |  |  |  |
Auto physical damage | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 108.3 | 108.3 | 108.9 | 109.0 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 94,500,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 108.3 | 108.3 | 109.1 | $ 103.6 |  |  |  |  |  |
Auto physical damage | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 110.0 | 110.5 | 111.6 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (0.2) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 92,200,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 110.1 | 110.7 | $ 106.2 |  |  |  |  |  |  |
Auto physical damage | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 86.9 | 87.0 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (0.8) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 68,800,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 87.6 | $ 84.1 |  |  |  |  |  |  |  |
Auto physical damage | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 105.0 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (6.7) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 69,700,000 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 97.3 |  |  |  |  |  |  |  |  |

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- Definition Short-duration Insurance Contracts, Incurred But Not Reported (IBNR) Claims Liability Plus Expected Development On Reported Claims, Net + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671311-158438 + Details
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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 Undiscounted amount, after reinsurance, of incurred claims and allocated claim adjustment expense used in claims development for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671311-158438 + Details
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- Definition Undiscounted amount, after reinsurance, of the liability for unpaid claims and allocated claim adjustment expense for short-duration insurance contracts. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671315-158438 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671311-158438 + Details
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- Definition Undiscounted amount, after reinsurance, of the liability for unpaid claims and allocated claim adjustment expense for short-duration insurance contracts for accident years not separately presented in claim development information. Excludes unallocated claim adjustment expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671311-158438 + Details
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- Definition Amount of reconciling item for the reconciliation of the liability in the disclosure of claims development (in excess of) less than the liability for unpaid claims and claims adjustment expense for short-duration insurance contracts, classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671315-158438 + Details
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- Definition Cumulative number of reported claims for short-duration insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671317-158438 + Details
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