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v3.24.3

Fair Value of Financial Instruments - Rollforward of Instruments Measured on Recurring Basis (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Financial Assets |  |  |  |
Beginning balance | $ 526.6 | $ 478.8 | $ 518.5 | $ 425.3
Transfers into Level 3 | 19.8 | 0.0 | 19.8 | 36.9
Transfers out of Level 3 | (7.9) | (3.7) | (12.3) | (3.7)
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | (0.4) | 0.2 | (0.1) | 0.2
Net unrealized gains (losses) included in OCI | (0.5) | (4.9) | (0.6) | (6.7)
Purchases | 24.3 | 19.2 | 67.8 | 54.6
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | 0.0 | 0.0 | 0.0 | (7.7)
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (13.8) | (12.0) | (45.0) | (21.3)
Ending balance | 548.1 | 477.6 | 548.1 | 477.6
Financial Liabilities |  |  |  |
Beginning balance | 77.9 | 83.6 | 82.4 | 91.3
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 | 6.6 | (3.2) | 7.6 | (5.6)
Net unrealized gains (losses) included in OCI | 0.2 | 0.4 | 0.2 | (0.3)
Purchases | 0.0 | 0.0 | 0.0 | 0.0
Issuances | 0.8 | 2.0 | 3.6 | 6.3
Sales | 0.0 | 0.0 | 0.0 | 0.0
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (4.4) | (4.5) | (12.7) | (13.4)
Ending balance | $ 81.1 | $ 78.3 | $ 81.1 | $ 78.3
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
Level 3 |  |  |  |
Total gains or losses |  |  |  |
Net investment (gains) losses included in net income related to financial liabilities | $ 0.4 | $ (0.2) | $ (0.1) | $ (0.2)
Municipal bonds |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 72.1 | 63.9 | 74.0 | 54.4
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 | 0.0 | 0.0 | 0.0 | 0.0
Net unrealized gains (losses) included in OCI | 1.4 | 5.9 | 0.0 | 6.5
Purchases | 3.2 | 0.0 | 3.2 | 9.5
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 | (0.1) | (0.1) | (0.6) | (0.7)
Ending balance | 76.6 | 69.7 | 76.6 | 69.7
Corporate bonds |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 366.4 | 311.5 | 342.5 | 261.3
Transfers into Level 3 | 11.8 | 0.0 | 11.8 | 36.1
Transfers out of Level 3 | (3.9) | (3.7) | (8.3) | (3.7)
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | 0.0 | 0.0 | (0.8) | 0.0
Net unrealized gains (losses) included in OCI | (3.4) | (12.8) | (3.6) | (14.1)
Purchases | 19.9 | 17.5 | 61.6 | 43.2
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | 0.0 | 0.0 | 0.0 | (7.7)
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (8.0) | (7.3) | (20.4) | (9.9)
Ending balance | 382.8 | 305.2 | 382.8 | 305.2
Mortgage Backed and Other Asset- Backed Securities |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 85.4 | 101.4 | 97.5 | 107.6
Transfers into Level 3 | 8.0 | 0.0 | 8.0 | 0.8
Transfers out of Level 3 | (4.0) | 0.0 | (4.0) | 0.0
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | (0.5) | 0.0 | 0.3 | 0.0
Net unrealized gains (losses) included in OCI | 1.5 | 2.0 | 3.0 | 0.9
Purchases | 0.0 | 1.7 | 1.8 | 1.9
Issuances | 0.0 | 0.0 | 0.0 |
Sales | 0.0 | 0.0 | 0.0 |
Settlements | 0.0 | 0.0 | 0.0 |
Paydowns, maturities and distributions | (5.7) | (4.6) | (21.9) | (10.7)
Ending balance | 84.7 | 100.5 | 84.7 | 100.5
Total Fixed Maturity Securities |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 523.9 | 476.8 | 514.0 | 423.3
Transfers into Level 3 | 19.8 | 0.0 | 19.8 | 36.9
Transfers out of Level 3 | (7.9) | (3.7) | (12.3) | (3.7)
Total gains or losses |  |  |  |
Net investment gains (losses) included in net income | (0.5) | 0.0 | (0.5) | 0.0
Net unrealized gains (losses) included in OCI | (0.5) | (4.9) | (0.6) | (6.7)
Purchases | 23.1 | 19.2 | 66.6 | 54.6
Issuances | 0.0 | 0.0 | 0.0 | 0.0
Sales | 0.0 | 0.0 | 0.0 | (7.7)
Settlements | 0.0 | 0.0 | 0.0 | 0.0
Paydowns, maturities and distributions | (13.8) | (12.0) | (42.9) | (21.3)
Ending balance | 544.1 | 475.4 | 544.1 | 475.4
Equity securities |  |  |  |
Financial Assets |  |  |  |
Beginning balance | 2.7 | 2.0 | 4.5 | 2.0
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 | 0.1 | 0.2 | 0.4 | 0.2
Net unrealized gains (losses) included in OCI | 0.0 | 0.0 | 0.0 | 0.0
Purchases | 1.2 | 0.0 | 1.2 | 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 | (2.1) | 0.0
Ending balance | $ 4.0 | $ 2.2 | $ 4.0 | $ 2.2

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