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v3.25.1

Fair Value of Financial Instruments - Rollforward of Instruments Measured on Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Total gains or losses |  |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net investment gains (losses) | Net investment gains (losses)
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent | Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent
Level 3 |  |
Financial Assets |  |
Beginning balance | $ 533.0 | $ 518.5
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | (4.4)
Total gains or losses |  |
Net investment gains (losses) included in net income | 5.8 | 0.1
Net unrealized gains (losses) included in OCI | 0.1 | 1.1
Purchases | 13.4 | 14.1
Issuances | 0.0 | 0.0
Sales | (22.6) | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | (6.7) | (19.5)
Ending balance | 523.0 | 509.9
Financial Liabilities |  |
Beginning balance | 75.5 | 82.4
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0
Total gains or losses |  |
Net investment (gains) losses included in net income related to financial liabilities | 1.9 | 1.3
Net unrealized gains (losses) included in OCI | 0.2 | (0.1)
Purchases | 0.0 | 0.0
Issuances | 1.4 | 1.4
Sales | 0.0 | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | (4.7) | (4.2)
Ending balance | 74.3 | 80.8
Level 3 | Municipal bonds |  |
Financial Assets |  |
Beginning balance | 74.9 | 74.0
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0
Total gains or losses |  |
Net investment gains (losses) included in net income | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | 1.3 | (0.7)
Purchases | 0.0 | 0.0
Issuances | 0.0 | 0.0
Sales | 0.0 | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | (0.1) | (0.1)
Ending balance | 76.1 | 73.2
Level 3 | Corporate bonds |  |
Financial Assets |  |
Beginning balance | 351.3 | 342.5
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | (4.4)
Total gains or losses |  |
Net investment gains (losses) included in net income | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | (0.6) | (0.6)
Purchases | 13.4 | 14.1
Issuances | 0.0 | 0.0
Sales | (22.4) | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | (0.8) | (6.1)
Ending balance | 340.9 | 345.5
Level 3 | Mortgage Backed and Other Asset- Backed Securities |  |
Financial Assets |  |
Beginning balance | 73.7 | 97.5
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0
Total gains or losses |  |
Net investment gains (losses) included in net income | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | (0.6) | 2.4
Purchases | 0.0 | 0.0
Issuances | 0.0 | 0.0
Sales | (0.2) | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | (5.8) | (11.2)
Ending balance | 67.1 | 88.7
Level 3 | Total Fixed Maturity Securities |  |
Financial Assets |  |
Beginning balance | 499.9 | 514.0
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | (4.4)
Total gains or losses |  |
Net investment gains (losses) included in net income | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | 0.1 | 1.1
Purchases | 13.4 | 14.1
Issuances | 0.0 | 0.0
Sales | (22.6) | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | (6.7) | (17.4)
Ending balance | 484.1 | 507.4
Level 3 | Equity Securities & Limited Partnership Interests |  |
Financial Assets |  |
Beginning balance | 33.1 | 4.5
Transfers into Level 3 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0
Total gains or losses |  |
Net investment gains (losses) included in net income | 5.8 | 0.1
Net unrealized gains (losses) included in OCI | 0.0 | 0.0
Purchases | 0.0 | 0.0
Issuances | 0.0 | 0.0
Sales | 0.0 | 0.0
Settlements | 0.0 | 0.0
Paydowns, maturities and distributions | 0.0 | (2.1)
Ending balance | $ 38.9 | $ 2.5

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