XML 61 R45.htm IDEA: XBRL DOCUMENT v3.24.3
Fair Value of Financial Instruments - Financial Instruments Measured and Carried at Fair Value (Details) - USD ($)
$ in Millions
Sep. 30, 2024
Dec. 31, 2023
Financial Assets    
Total fixed maturity securities $ 5,573.2 $ 5,235.3
Equity securities 88.9 86.2
Mortgage-backed securities    
Financial Assets    
Total fixed maturity securities 728.3 653.2
Other, including U.S. Treasury securities    
Financial Assets    
Total fixed maturity securities 385.7 388.8
Municipal bonds    
Financial Assets    
Total fixed maturity securities 1,215.7 1,270.1
Foreign government bonds    
Financial Assets    
Total fixed maturity securities 16.5 22.1
Corporate bonds    
Financial Assets    
Total fixed maturity securities 1,944.5 1,772.7
Other asset-backed securities    
Financial Assets    
Total fixed maturity securities 1,282.5 1,128.4
Carrying Amount | Recurring    
Financial Assets    
Total fixed maturity securities 5,573.2 5,235.3
Equity securities 88.9 86.2
Short-term investments 91.6 132.9
Other investments 22.5 19.0
Totals 5,776.2 5,473.4
Separate Account variable annuity assets 3,732.8 3,294.1
Financial Liabilities 86.1 86.0
Carrying Amount | Recurring | Mortgage-backed securities    
Financial Assets    
Total fixed maturity securities 728.3 653.2
Carrying Amount | Recurring | Other, including U.S. Treasury securities    
Financial Assets    
Total fixed maturity securities 385.7 388.8
Carrying Amount | Recurring | Municipal bonds    
Financial Assets    
Total fixed maturity securities 1,215.7 1,270.1
Carrying Amount | Recurring | Foreign government bonds    
Financial Assets    
Total fixed maturity securities 16.5 22.1
Carrying Amount | Recurring | Corporate bonds    
Financial Assets    
Total fixed maturity securities 1,944.5 1,772.7
Carrying Amount | Recurring | Other asset-backed securities    
Financial Assets    
Total fixed maturity securities 1,282.5 1,128.4
Fair Value | Recurring    
Financial Assets    
Total fixed maturity securities 5,573.2 5,235.3
Equity securities 88.9 86.2
Short-term investments 91.6 132.9
Other investments 22.5 19.0
Totals 5,776.2 5,473.4
Separate Account variable annuity assets 3,732.8 3,294.1
Financial Liabilities 86.1 86.0
Fair Value | Recurring | Level 1    
Financial Assets    
Total fixed maturity securities 33.5 55.7
Equity securities 19.5 17.9
Short-term investments 91.6 132.9
Other investments 0.0 0.0
Totals 144.6 206.5
Separate Account variable annuity assets 3,732.8 3,294.1
Financial Liabilities 0.0 0.0
Fair Value | Recurring | Level 2    
Financial Assets    
Total fixed maturity securities 4,995.6 4,665.6
Equity securities 65.4 63.8
Short-term investments 0.0 0.0
Other investments 22.5 19.0
Totals 5,083.5 4,748.4
Separate Account variable annuity assets 0.0 0.0
Financial Liabilities 5.0 3.6
Fair Value | Recurring | Level 3    
Financial Assets    
Total fixed maturity securities 544.1 514.0
Equity securities 4.0 4.5
Short-term investments 0.0 0.0
Other investments 0.0 0.0
Totals 548.1 518.5
Separate Account variable annuity assets 0.0 0.0
Financial Liabilities 81.1 82.4
Fair Value | Recurring | Mortgage-backed securities    
Financial Assets    
Total fixed maturity securities 728.3 653.2
Fair Value | Recurring | Mortgage-backed securities | Level 1    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Mortgage-backed securities | Level 2    
Financial Assets    
Total fixed maturity securities 728.3 653.2
Fair Value | Recurring | Mortgage-backed securities | Level 3    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Other, including U.S. Treasury securities    
Financial Assets    
Total fixed maturity securities 385.7 388.8
Fair Value | Recurring | Other, including U.S. Treasury securities | Level 1    
Financial Assets    
Total fixed maturity securities 25.3 45.6
Fair Value | Recurring | Other, including U.S. Treasury securities | Level 2    
Financial Assets    
Total fixed maturity securities 360.4 343.2
Fair Value | Recurring | Other, including U.S. Treasury securities | Level 3    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Municipal bonds    
Financial Assets    
Total fixed maturity securities 1,215.7 1,270.1
Fair Value | Recurring | Municipal bonds | Level 1    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Municipal bonds | Level 2    
Financial Assets    
Total fixed maturity securities 1,139.1 1,196.1
Fair Value | Recurring | Municipal bonds | Level 3    
Financial Assets    
Total fixed maturity securities 76.6 74.0
Fair Value | Recurring | Foreign government bonds    
Financial Assets    
Total fixed maturity securities 16.5 22.1
Fair Value | Recurring | Foreign government bonds | Level 1    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Foreign government bonds | Level 2    
Financial Assets    
Total fixed maturity securities 16.5 22.1
Fair Value | Recurring | Foreign government bonds | Level 3    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Corporate bonds    
Financial Assets    
Total fixed maturity securities 1,944.5 1,772.7
Fair Value | Recurring | Corporate bonds | Level 1    
Financial Assets    
Total fixed maturity securities 8.2 10.1
Fair Value | Recurring | Corporate bonds | Level 2    
Financial Assets    
Total fixed maturity securities 1,553.5 1,420.1
Fair Value | Recurring | Corporate bonds | Level 3    
Financial Assets    
Total fixed maturity securities 382.8 342.5
Fair Value | Recurring | Other asset-backed securities    
Financial Assets    
Total fixed maturity securities 1,282.5 1,128.4
Fair Value | Recurring | Other asset-backed securities | Level 1    
Financial Assets    
Total fixed maturity securities 0.0 0.0
Fair Value | Recurring | Other asset-backed securities | Level 2    
Financial Assets    
Total fixed maturity securities 1,197.8 1,030.9
Fair Value | Recurring | Other asset-backed securities | Level 3    
Financial Assets    
Total fixed maturity securities $ 84.7 $ 97.5