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v3.25.2

Fair Value of Financial Instruments - Rollforward of Instruments Measured on Recurring Basis (Details) - Level 3 - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Financial Assets |  |  |  |
Beginning balance | $ 523.0 | $ 509.9 | $ 533.0 | $ 518.5
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | (4.4)
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | (0.9) | 0.2 | 4.9 | 0.3
Net unrealized gains (losses) included in OCI | 2.8 | (1.2) | 3.0 | (0.1)
Purchases | 8.9 | 29.4 | 22.3 | 43.5
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | (4.7) | 0.0 | (27.1) | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (10.1) | (11.7) | (17.1) | (31.2)
Ending balance | 519.0 | 526.6 | 519.0 | 526.6
Financial Liabilities |  |  |  |
Beginning balance | 74.3 | 80.8 | 75.5 | 82.4
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Total gains or losses |  |  |  |
Net investment (gains) losses included in net income related to financial liabilities | 3.7 | (0.3) | 5.6 | 1.0
Net unrealized gains (losses) included in OCI | (0.4) | 0.1 | (0.2) | 0.0
Purchases | 0.0 | 0.0 | 0.0 | 0.0
Issuances | 0.7 | 1.4 | 2.1 | 2.8
Sales | 0.0 | 0.0 | 0.0 | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (4.3) | (4.1) | (9.0) | (8.3)
Ending balance | $ 74.0 | $ 77.9 | $ 74.0 | $ 77.9
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) | 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 | 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 | 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
Municipal bonds |  |  |  |
Financial Assets |  |  |  |
Beginning balance | $ 76.1 | $ 73.2 | $ 74.9 | $ 74.0
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | 0.0 | 0.0 | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | 0.1 | (0.7) | 1.5 | (1.4)
Purchases | 0.0 | 0.0 | 0.0 | 0.0
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | 0.0 | 0.0 | 0.0 | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (0.3) | (0.4) | (0.5) | (0.5)
Ending balance | 75.9 | 72.1 | 75.9 | 72.1
Corporate bonds |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 340.9 | 345.5 | 351.3 | 342.5
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | (4.4)
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | 0.0 | (0.8) | 0.0 | (0.8)
Net unrealized gains (losses) included in OCI | 2.4 | 0.4 | 1.8 | (0.2)
Purchases | 8.9 | 27.6 | 22.3 | 41.7
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | (3.0) | 0.0 | (25.3) | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (7.3) | (6.3) | (8.1) | (12.4)
Ending balance | 342.0 | 366.4 | 342.0 | 366.4
Mortgage Backed and Other Asset- Backed Securities |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 67.1 | 88.7 | 73.7 | 97.5
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | 0.0 | 0.8 | 0.0 | 0.8
Net unrealized gains (losses) included in OCI | 0.3 | (0.9) | (0.2) | 1.5
Purchases | 0.0 | 1.8 | 0.0 | 1.8
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | (1.7) | 0.0 | (1.8) | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (2.5) | (5.0) | (8.5) | (16.2)
Ending balance | 63.2 | 85.4 | 63.2 | 85.4
Total Fixed Maturity Securities |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 484.1 | 507.4 | 499.9 | 514.0
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | (4.4)
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | 0.0 | 0.0 | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | 2.8 | (1.2) | 3.0 | (0.1)
Purchases | 8.9 | 29.4 | 22.3 | 43.5
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | (4.7) | 0.0 | (27.1) | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (10.1) | (11.7) | (17.1) | (29.1)
Ending balance | 481.0 | 523.9 | 481.0 | 523.9
Equity Securities & Limited Partnership Interests |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 38.9 | 2.5 | 33.1 | 4.5
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | (0.9) | 0.2 | 4.9 | 0.3
Net unrealized gains (losses) included in OCI | 0.0 | 0.0 | 0.0 | 0.0
Purchases | 0.0 | 0.0 | 0.0 | 0.0
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | 0.0 | 0.0 | 0.0 | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | 0.0 | 0.0 | 0.0 | (2.1)
Ending balance | $ 38.0 | $ 2.7 | $ 38.0 | $ 2.7

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