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v3.25.0.1

Fair Value Measurements - Level 3 Inputs Reconciliation (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | $ 192.3 | $ 230.0
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | $ 2.8 | (1.5)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net Realized Investment Gains (Losses) |
Included in Other Comprehensive Income | $ 0.2 | 6.8
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] | Changes in Unrealized (Losses) Gains on Investment Securities with: |
Purchases | $ 133.4 | 51.6
Sales | (105.7) | (102.6)
Transfers into Level 3 | 10.6 | 8.1
Transfers out of Level 3 | (24.6) | (0.1)
Balance, End of Year | 209.0 | 192.3
Bonds and Notes |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | 177.1 | 216.0
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | 0.6 | (0.7)
Included in Other Comprehensive Income | 0.8 | 6.4
Purchases | 124.2 | 50.4
Sales | (104.0) | (102.6)
Transfers into Level 3 | 7.1 | 7.7
Transfers out of Level 3 | (11.6) | (0.1)
Balance, End of Year | 194.2 | 177.1
States and Political Subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | 0.1 | 0.0
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | 0.0 | 0.0
Included in Other Comprehensive Income | (0.5) | 0.0
Purchases | 0.0 | 0.1
Sales | 0.0 | 0.0
Transfers into Level 3 | 3.5 | 0.0
Transfers out of Level 3 | (1.3) | 0.0
Balance, End of Year | 1.8 | 0.1
Redeemable Preferred Stocks |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | 7.1 | 6.8
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | 0.0 | 0.0
Included in Other Comprehensive Income | 0.1 | 0.3
Purchases | 1.9 | 0.0
Sales | 0.0 | 0.0
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | (4.9) | 0.0
Balance, End of Year | 4.2 | 7.1
Collateralized Loan Obligations |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | 0.0 |
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | 0.0 |
Included in Other Comprehensive Income | 0.0 |
Purchases | 6.8 |
Sales | 0.0 |
Transfers into Level 3 | 0.0 |
Transfers out of Level 3 | (6.8) |
Balance, End of Year | 0.0 | 0.0
Other Mortgage- and Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | 5.2 | 5.1
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | 0.0 | 0.0
Included in Other Comprehensive Income | (0.2) | 0.1
Purchases | 0.0 | 0.0
Sales | 0.0 | 0.0
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0
Balance, End of Year | 5.0 | 5.2
Equity Securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning of Year | 2.8 | 2.1
Total Gains (Losses): |  |
Included in Consolidated Statements of Income (Loss) | 2.2 | (0.8)
Included in Other Comprehensive Income | 0.0 | 0.0
Purchases | 0.5 | 1.1
Sales | (1.7) | 0.0
Transfers into Level 3 | 0.0 | 0.4
Transfers out of Level 3 | 0.0 | 0.0
Balance, End of Year | $ 3.8 | $ 2.8

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