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SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) $ in Millions | Dec. 31, 2025 USD ($)
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Summary of investments other than investments in related parties |
Cost or Amortized Cost | $ 7,478.3
Carrying Value | 8,324.9
Fair Value | 8,324.9
Fixed maturity investments |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 2,774.8
Carrying Value | 2,770.5
Fair Value | 2,770.5
U.S. Government and agency obligations |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 459.7
Carrying Value | 460.3
Fair Value | 460.3
Debt securities issued by corporations |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 1,534.9
Carrying Value | 1,537.7
Fair Value | 1,537.7
Mortgage and asset-backed securities |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 405.1
Carrying Value | 393.0
Fair Value | 393.0
Collateralized loan obligations |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 343.9
Carrying Value | 347.0
Fair Value | 347.0
Foreign government and agency obligations |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 31.2
Carrying Value | 32.5
Fair Value | 32.5
Short-term investments |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 1,881.2
Carrying Value | 1,881.7
Fair Value | 1,881.7
Equity Method Investments |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 1,727.3
Carrying Value | 2,375.1
Equity Method Investments | MediaAlpha |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 59.2
Carrying Value | 231.2
Fair Value | 231.2
Industrial, Miscellaneous and Other |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 353.7
Carrying Value | 452.3
Fair Value | 452.3
Exchange-traded funds |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 30.6
Carrying Value | 30.7
Fair Value | 30.7
Total common equity securities |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 384.3
Carrying Value | 483.0
Fair Value | 483.0
Other long-term investments |
Summary of investments other than investments in related parties |
Cost or Amortized Cost | 2,378.8
Carrying Value | 2,958.5
Fair Value | $ 2,958.5

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