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Short-Duration Insurance Contracts - Incurred and Paid Claims by Accident Year on a Net Basis (Details) $ in Millions | Dec. 31, 2023 USD ($) claim | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
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Homeowners |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 1,398.3 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,324.9 |  |  |  |  |  |  |  |  |
Outstanding prior to 2013 | 0.0 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 73.4 |  |  |  |  |  |  |  |  |
Homeowners | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 106.4 | $ 106.4 | $ 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 | 19,777 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 106.4 | 106.4 | 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 [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 114.9 | 114.9 | 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 | 19,745 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 114.9 | 114.7 | 114.7 | 114.9 | 114.6 | 113.3 | 111.9 | 109.3 | 90.7 |
Homeowners | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 118.1 | 118.1 | 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 | 19,662 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 118.1 | 118.0 | 117.8 | 117.7 | 117.5 | 115.1 | 113.2 | 95.8 |  |
Homeowners | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 131.3 | 130.8 | 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 | 19,741 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 131.2 | 130.7 | 130.5 | 130.0 | 129.8 | 128.5 | 106.8 |  |  |
Homeowners | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 156.0 | 157.2 | 158.1 | 158.9 | 157.4 | 166.8 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 20,296 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 156.2 | 157.2 | 157.4 | 157.0 | 152.4 | 130.5 |  |  |  |
Homeowners | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 131.1 | 130.9 | 132.1 | 129.9 | 130.4 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 18,114 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 130.4 | 130.0 | 129.1 | 126.2 | 103.8 |  |  |  |  |
Homeowners | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 146.9 | 145.4 | 151.9 | 155.7 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 18,906 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 145.6 | 144.0 | 138.7 | 106.8 |  |  |  |  |  |
Homeowners | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 154.3 | 150.7 | 150.2 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1.9 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 18,056 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 151.0 | 146.3 | 114.9 |  |  |  |  |  |  |
Homeowners | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 156.2 | 162.2 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 8.4 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 15,036 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 144.8 | 108.3 |  |  |  |  |  |  |  |
Homeowners | 2023 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 183.1 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 38.8 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 14,655 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 126.3 |  |  |  |  |  |  |  |  |
Auto liability |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,731.0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,531.2 |  |  |  |  |  |  |  |  |
Outstanding prior to 2013 | 1.1 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 200.9 |  |  |  |  |  |  |  |  |
Auto liability | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 160.1 | 160.0 | 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 | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 64,648 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 160.0 | 160.0 | 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 [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 178.9 | 178.8 | 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 | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 68,626 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 178.6 | 178.3 | 177.7 | 176.7 | 174.5 | 170.1 | 158.0 | 134.5 | 70.8 |
Auto liability | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 189.5 | 189.6 | 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 | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 70,684 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 189.4 | 189.0 | 188.1 | 184.5 | 177.8 | 166.8 | 140.9 | 73.1 |  |
Auto liability | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 192.5 | 192.9 | 191.7 | 189.1 | 188.6 | 188.8 | 188.0 |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 68,371 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 191.8 | 190.8 | 185.8 | 179.8 | 166.6 | 139.5 | 70.7 |  |  |
Auto liability | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 192.3 | 192.0 | 189.8 | 192.9 | 195.3 | 200.3 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1.1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 35,394 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 190.6 | 188.0 | 180.7 | 168.6 | 141.5 | 77.5 |  |  |  |
Auto liability | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 181.2 | 181.5 | 176.7 | 180.1 | 181.1 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 3.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 61,879 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 176.2 | 170.9 | 155.5 | 129.1 | 69.7 |  |  |  |  |
Auto liability | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 137.3 | 136.3 | 134.9 | 137.0 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 4.7 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 46,934 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 129.2 | 118.2 | 94.0 | 51.5 |  |  |  |  |  |
Auto liability | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 156.7 | 157.8 | 142.2 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 11.5 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 45,005 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 136.5 | 112.5 | 52.9 |  |  |  |  |  |  |
Auto liability | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 166.1 | 165.6 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 26.9 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 46,104 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 116.7 | 55.8 |  |  |  |  |  |  |  |
Auto liability | 2023 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 176.4 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 70.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 42,198 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 62.2 |  |  |  |  |  |  |  |  |
Auto physical damage |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,081.2 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 1,070.2 |  |  |  |  |  |  |  |  |
Outstanding prior to 2013 | 0.0 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 11.0 |  |  |  |  |  |  |  |  |
Auto physical damage | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 95.2 | 95.2 | 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 | 68,139 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 95.2 | 95.2 | 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 [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 97.6 | 97.6 | 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 | 70,685 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 97.6 | 97.6 | 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 [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 109.6 | 109.5 | 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 | 74,209 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 109.5 | 109.5 | 109.6 | 109.6 | 109.6 | 109.5 | 109.7 | 106.5 |  |
Auto physical damage | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 110.6 | 110.6 | 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 | 73,998 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 110.6 | 110.6 | 110.6 | 110.6 | 110.7 | 110.8 | 105.2 |  |  |
Auto physical damage | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 108.3 | 108.2 | 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 | 72,833 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 108.2 | 108.2 | 108.3 | 108.3 | 109.1 | 103.6 |  |  |  |
Auto physical damage | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 109.9 | 110.0 | 110.0 | 110.5 | 111.6 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (0.1) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 73,128 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 110.1 | 110.1 | 110.1 | 110.7 | 106.2 |  |  |  |  |
Auto physical damage | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 87.0 | 87.1 | 86.9 | 87.0 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (0.3) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 62,044 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 87.3 | 87.4 | 87.6 | 84.1 |  |  |  |  |  |
Auto physical damage | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 105.1 | 105.7 | 105.0 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (0.4) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 58,080 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 105.4 | 105.8 | 97.3 |  |  |  |  |  |  |
Auto physical damage | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 125.5 | 125.7 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.9 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 59,353 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 124.3 | 114.6 |  |  |  |  |  |  |  |
Auto physical damage | 2023 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 132.4 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (6.0) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 58,167 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 122.0 |  |  |  |  |  |  |  |  |
Specialty health |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 185.0 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 174.1 |  |  |  |  |  |  |  |  |
Outstanding prior to 2013 | 0.0 |  |  |  |  |  |  |  |  |
Prior years paid | 0.0 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 10.9 |  |  |  |  |  |  |  |  |
Specialty health | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 56.0 | 56.0 | 56.0 | 56.0 | 56.0 | 56.0 | 56.0 | 55.9 | 56.3 | 59.6
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 337,987 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 56.0 | 56.0 | 56.0 | 56.0 | 56.0 | 55.9 | 55.7 | 55.4 | 54.9 | 43.4
Specialty health | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 30.4 | 30.4 | 30.4 | 30.4 | 30.3 | 30.3 | 30.3 | 30.9 | 33.3 |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 183,433 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 30.4 | 30.4 | 30.4 | 30.4 | 30.3 | 30.3 | 30.3 | 30.4 | 24.9 |
Specialty health | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 11.1 | 11.1 | 11.1 | 11.1 | 11.1 | 11.1 | 11.2 | 12.5 |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 67,274 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 11.1 | 11.1 | 11.1 | 11.1 | 11.1 | 11.1 | 11.0 | 5.5 |  |
Specialty health | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 9.6 | 9.6 | 9.6 | 9.6 | 9.6 | 9.7 | 10.6 |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 63,492 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 9.6 | 9.6 | 9.6 | 9.6 | 9.6 | 9.4 | 7.3 |  |  |
Specialty health | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 12.6 | 12.6 | 12.7 | 13.0 | 13.2 | 12.9 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 95,218 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 12.6 | 12.6 | 12.6 | 12.5 | 12.1 | 8.8 |  |  |  |
Specialty health | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 9.5 | 9.5 | 9.6 | 9.5 | 10.6 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 72,754 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 9.5 | 9.5 | 9.5 | 9.3 | 7.5 |  |  |  |  |
Specialty health | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 5.7 | 5.7 | 5.8 | 6.8 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 43,609 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 5.7 | 5.7 | 5.6 | 4.2 |  |  |  |  |  |
Specialty health | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 16.1 | 17.7 | 22.8 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2.4 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 72,407 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 13.7 | 12.9 | 2.9 |  |  |  |  |  |  |
Specialty health | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 18.0 | 22.6 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 1.3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 120,965 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 16.7 | 10.5 |  |  |  |  |  |  |  |
Specialty health | 2023 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 16.0 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 7.1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 79,654 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 8.8 |  |  |  |  |  |  |  |  |
Group disability |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 280.8 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 206.6 |  |  |  |  |  |  |  |  |
Outstanding prior to 2013 | 9.0 |  |  |  |  |  |  |  |  |
Prior years paid | 100.3 |  |  |  |  |  |  |  |  |
Liabilities for claims and claim adjustment expenses, net of reinsurance | 83.2 |  |  |  |  |  |  |  |  |
Effect of discounting | (14.0) |  |  |  |  |  |  |  |  |
Discounted net reserves | 69.2 |  |  |  |  |  |  |  |  |
Group disability | 2014 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 14.5 | 14.6 | 14.3 | 14.7 | 14.5 | 14.3 | 14.4 | 14.8 | 13.3 | 16.3
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 2,863 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 12.9 | 12.7 | 12.4 | 12.1 | 11.7 | 11.1 | 10.6 | 9.9 | 8.5 | $ 3.7
Group disability | 2015 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 14.5 | 14.7 | 15.2 | 15.2 | 14.6 | 14.7 | 16.6 | 19.2 | 25.3 |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,347 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 19.1 | 18.9 | 18.6 | 18.1 | 17.6 | 17.2 | 16.6 | 14.0 | $ 6.8 |
Group disability | 2016 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 28.1 | 28.1 | 26.8 | 26.3 | 26.0 | 27.4 | 28.6 | 28.5 |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.7 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,618 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 22.9 | 22.4 | 21.8 | 21.1 | 20.3 | 19.3 | 16.4 | $ 8.3 |  |
Group disability | 2017 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 23.1 | 24.0 | 23.3 | 22.4 | 22.9 | 26.0 | 29.9 |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.1 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,904 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 19.7 | 19.4 | 18.9 | 18.3 | 17.9 | 16.1 | $ 8.5 |  |  |
Group disability | 2018 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 23.6 | 23.3 | 22.7 | 23.2 | 26.6 | 29.8 |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.3 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4,171 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 20.1 | 19.6 | 18.9 | 18.0 | 16.1 | $ 8.4 |  |  |  |
Group disability | 2019 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 30.2 | 29.9 | 30.2 | 33.5 | 34.5 |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.5 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4,549 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 25.2 | 24.7 | 24.3 | 22.8 | $ 11.8 |  |  |  |  |
Group disability | 2020 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 33.2 | 34.1 | 34.3 | 36.7 |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 0.6 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4,343 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 26.4 | 25.5 | 22.7 | $ 12.4 |  |  |  |  |  |
Group disability | 2021 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 41.3 | 41.3 | 37.8 |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 2.0 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 5,109 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 26.7 | 24.0 | $ 11.8 |  |  |  |  |  |  |
Group disability | 2022 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 32.0 | 39.2 |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ (0.5) |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 4,349 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 21.4 | $ 11.7 |  |  |  |  |  |  |  |
Group disability | 2023 |  |  |  |  |  |  |  |  |  |
Short-duration Insurance Contracts, Historical Claims Duration [Line Items] |  |  |  |  |  |  |  |  |  |
Incurred Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | 40.3 |  |  |  |  |  |  |  |  |
Total of Incurred- But-Not-Reported Liabilities Plus Expected Development on Reported Claims | $ 13.2 |  |  |  |  |  |  |  |  |
Cumulative Number of Reported Claims | claim | 3,510 |  |  |  |  |  |  |  |  |
Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net of Reinsurance | $ 12.2 |  |  |  |  |  |  |  |  |

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