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v3.25.4

Investments (Tables) | 12 Months Ended
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Dec. 31, 2025
Investments, Debt and Equity Securities [Abstract] |
Schedule of Available-for-sale Fixed Maturities Reconciliation | The amortized cost and fair value of available-for-sale fixed maturities were as follows:
DECEMBER 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
(in millions) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
|  | Amortized Cost |  |  | Allowance for Credit Losses |  |  | Amortized Cost, Net of Allowance for Credit Losses |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
U.S. Treasury and government agencies |  | $ | 491.3 |  |  | $ | — |  |  | $ | 491.3 |  |  | $ | 2.4 |  |  | $ | 38.2 |  |  | $ | 455.5 |
Foreign governments |  |  | 2.5 |  |  |  | — |  |  |  | 2.5 |  |  |  | 0.2 |  |  |  | — |  |  |  | 2.7 |
Municipals |  |  | 910.8 |  |  |  | — |  |  |  | 910.8 |  |  |  | 4.1 |  |  |  | 67.2 |  |  |  | 847.7 |
Corporates |  |  | 4,239.3 |  |  |  | (0.2 | ) |  |  | 4,239.1 |  |  |  | 71.4 |  |  |  | 57.0 |  |  |  | 4,253.5 |
Residential mortgage-backed |  |  | 2,472.2 |  |  |  | — |  |  |  | 2,472.2 |  |  |  | 32.4 |  |  |  | 82.8 |  |  |  | 2,421.8 |
Commercial mortgage-backed |  |  | 610.2 |  |  |  | — |  |  |  | 610.2 |  |  |  | 1.0 |  |  |  | 21.3 |  |  |  | 589.9 |
Other asset-backed |  |  | 959.6 |  |  |  | — |  |  |  | 959.6 |  |  |  | 6.5 |  |  |  | 0.7 |  |  |  | 965.4 |
Total fixed maturities |  | $ | 9,685.9 |  |  | $ | (0.2 | ) |  | $ | 9,685.7 |  |  | $ | 118.0 |  |  | $ | 267.2 |  |  | $ | 9,536.5 |
DECEMBER 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
(in millions) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
|  | Amortized Cost |  |  | Allowance for Credit Losses |  |  | Amortized Cost, Net of Allowance for Credit Losses |  |  | Gross Unrealized Gains |  |  | Gross Unrealized Losses |  |  | Fair Value |
U.S. Treasury and government agencies |  | $ | 552.6 |  |  | $ | — |  |  | $ | 552.6 |  |  | $ | 0.4 |  |  | $ | 58.8 |  |  | $ | 494.2 |
Foreign governments |  |  | 1.8 |  |  |  | — |  |  |  | 1.8 |  |  |  | 0.1 |  |  |  | — |  |  |  | 1.9 |
Municipals |  |  | 1,001.5 |  |  |  | — |  |  |  | 1,001.5 |  |  |  | 1.5 |  |  |  | 109.2 |  |  |  | 893.8 |
Corporates |  |  | 3,953.5 |  |  |  | (0.6 | ) |  |  | 3,952.9 |  |  |  | 14.4 |  |  |  | 161.4 |  |  |  | 3,805.9 |
Residential mortgage-backed |  |  | 2,277.6 |  |  |  | — |  |  |  | 2,277.6 |  |  |  | 2.8 |  |  |  | 156.3 |  |  |  | 2,124.1 |
Commercial mortgage-backed |  |  | 564.2 |  |  |  | — |  |  |  | 564.2 |  |  |  | 0.1 |  |  |  | 42.1 |  |  |  | 522.2 |
Other asset-backed |  |  | 700.9 |  |  |  | — |  |  |  | 700.9 |  |  |  | 2.5 |  |  |  | 3.3 |  |  |  | 700.1 |
Total fixed maturities |  | $ | 9,052.1 |  |  | $ | (0.6 | ) |  | $ | 9,051.5 |  |  | $ | 21.8 |  |  | $ | 531.1 |  |  | $ | 8,542.2 |
Investments Classified by Contractual Maturity Date | The amortized cost and fair value by maturity periods for fixed maturities are shown in the following table. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties, or the Company may have the right to put or sell the obligations back to the issuers.
DECEMBER 31 |  | 2025 |
(in millions) |  | Amortized Cost, net of Allowance for Credit Losses |  |  | Fair Value |
Due in one year or less |  | $ | 127.5 |  |  | $ | 127.5 |
Due after one year through five years |  |  | 2,361.7 |  |  |  | 2,351.2 |
Due after five years through ten years |  |  | 2,839.6 |  |  |  | 2,788.0 |
Due after ten years |  |  | 314.9 |  |  |  | 292.7 |
|  |  | 5,643.7 |  |  |  | 5,559.4 |
Mortgage-backed and other asset-backed securities |  |  | 4,042.0 |  |  |  | 3,977.1 |
Total fixed maturities |  | $ | 9,685.7 |  |  | $ | 9,536.5 |
Unrealized Gains and Losses on Available-for-Sale and Other Securities | Unrealized gains and losses on available-for-sale fixed maturities are summarized in the following table.
YEARS ENDED DECEMBER 31 |  |  |  |  |  |  |  |  |
(in millions) |  |  |  |  |  |  |  |  |
|  | 2025 |  |  | 2024 |  |  | 2023 |
Net depreciation, beginning of year |  | $ | (403.5 | ) |  | $ | (462.8 | ) |  | $ | (641.4 | )
Net appreciation on available-for-sale fixed maturities |  |  | 364.6 |  |  |  | 76.6 |  |  |  | 227.6 |
Provision for deferred income taxes |  |  | (77.4 | ) |  |  | (17.3 | ) |  |  | (49.0 | )
|  |  | 287.2 |  |  |  | 59.3 |  |  |  | 178.6 |
Net depreciation, end of year |  | $ | (116.3 | ) |  | $ | (403.5 | ) |  | $ | (462.8 | )
Schedule of Unrealized Loss on Investments | The following tables provide information about the Company’s available-for-sale fixed maturity securities that were in an unrealized loss position at December 31, 2025 and 2024, including the length of time the securities have been in an unrealized loss position:
DECEMBER 31, 2025 |  | 12 months or less |  |  | Greater than 12 months |  |  | Total |
(in millions) |  | Gross |  |  |  |  |  | Gross |  |  |  |  |  | Gross |  |  |  |
|  | Unrealized |  |  | Fair |  |  | Unrealized |  |  | Fair |  |  | Unrealized |  |  | Fair |
|  | Losses |  |  | Value |  |  | Losses |  |  | Value |  |  | Losses |  |  | Value |
Investment grade: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury and government agencies |  | $ | — |  |  | $ | 11.9 |  |  | $ | 38.2 |  |  | $ | 319.7 |  |  | $ | 38.2 |  |  | $ | 331.6 |
Municipals |  |  | 0.6 |  |  |  | 56.3 |  |  |  | 66.6 |  |  |  | 550.3 |  |  |  | 67.2 |  |  |  | 606.6 |
Corporates |  |  | 1.0 |  |  |  | 271.3 |  |  |  | 51.2 |  |  |  | 704.2 |  |  |  | 52.2 |  |  |  | 975.5 |
Residential mortgage-backed |  |  | 0.5 |  |  |  | 128.7 |  |  |  | 82.3 |  |  |  | 521.7 |  |  |  | 82.8 |  |  |  | 650.4 |
Commercial mortgage-backed |  |  | 0.5 |  |  |  | 122.5 |  |  |  | 20.0 |  |  |  | 284.3 |  |  |  | 20.5 |  |  |  | 406.8 |
Other asset-backed |  |  | 0.5 |  |  |  | 82.9 |  |  |  | 0.2 |  |  |  | 24.3 |  |  |  | 0.7 |  |  |  | 107.2 |
Total investment grade |  |  | 3.1 |  |  |  | 673.6 |  |  |  | 258.5 |  |  |  | 2,404.5 |  |  |  | 261.6 |  |  |  | 3,078.1 |
Below investment grade: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Corporates |  |  | 2.2 |  |  |  | 37.5 |  |  |  | 2.6 |  |  |  | 34.8 |  |  |  | 4.8 |  |  |  | 72.3 |
Commercial mortgage-backed |  |  | — |  |  |  | — |  |  |  | 0.8 |  |  |  | 4.9 |  |  |  | 0.8 |  |  |  | 4.9 |
Other asset-backed |  |  | — |  |  |  | 1.3 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 1.3 |
Total below investment grade |  |  | 2.2 |  |  |  | 38.8 |  |  |  | 3.4 |  |  |  | 39.7 |  |  |  | 5.6 |  |  |  | 78.5 |
Total fixed maturities |  | $ | 5.3 |  |  | $ | 712.4 |  |  | $ | 261.9 |  |  | $ | 2,444.2 |  |  | $ | 267.2 |  |  | $ | 3,156.6 |
DECEMBER 31, 2024 |  | 12 months or less |  |  | Greater than 12 months |  |  | Total |
(in millions) |  | Gross |  |  |  |  |  | Gross |  |  |  |  |  | Gross |  |  |  |
|  | Unrealized |  |  | Fair |  |  | Unrealized |  |  | Fair |  |  | Unrealized |  |  | Fair |
|  | Losses |  |  | Value |  |  | Losses |  |  | Value |  |  | Losses |  |  | Value |
Investment grade: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury and government agencies |  | $ | 7.8 |  |  | $ | 194.4 |  |  | $ | 51.0 |  |  | $ | 240.8 |  |  | $ | 58.8 |  |  | $ | 435.2 |
Municipals |  |  | 3.0 |  |  |  | 132.5 |  |  |  | 106.2 |  |  |  | 680.9 |  |  |  | 109.2 |  |  |  | 813.4 |
Corporates |  |  | 22.8 |  |  |  | 1,360.3 |  |  |  | 132.0 |  |  |  | 1,523.3 |  |  |  | 154.8 |  |  |  | 2,883.6 |
Residential mortgage-backed |  |  | 16.5 |  |  |  | 896.8 |  |  |  | 139.8 |  |  |  | 747.2 |  |  |  | 156.3 |  |  |  | 1,644.0 |
Commercial mortgage-backed |  |  | 0.7 |  |  |  | 23.7 |  |  |  | 41.4 |  |  |  | 485.4 |  |  |  | 42.1 |  |  |  | 509.1 |
Other asset-backed |  |  | 2.5 |  |  |  | 181.4 |  |  |  | 0.8 |  |  |  | 78.5 |  |  |  | 3.3 |  |  |  | 259.9 |
Total investment grade |  |  | 53.3 |  |  |  | 2,789.1 |  |  |  | 471.2 |  |  |  | 3,756.1 |  |  |  | 524.5 |  |  |  | 6,545.2 |
Below investment grade: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Foreign governments |  |  | — |  |  |  | 0.1 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 0.1 |
Corporates |  |  | 1.3 |  |  |  | 70.8 |  |  |  | 5.3 |  |  |  | 49.8 |  |  |  | 6.6 |  |  |  | 120.6 |
Commercial mortgage-backed |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 0.8 |  |  |  | — |  |  |  | 0.8 |
Total below investment grade |  |  | 1.3 |  |  |  | 70.9 |  |  |  | 5.3 |  |  |  | 50.6 |  |  |  | 6.6 |  |  |  | 121.5 |
Total fixed maturities |  | $ | 54.6 |  |  | $ | 2,860.0 |  |  | $ | 476.5 |  |  | $ | 3,806.7 |  |  | $ | 531.1 |  |  | $ | 6,666.7 |
Schedule of Other Investments | Mortgage participations and other mortgage loans were comprised of the following property types and geographic locations
DECEMBER 31 |  | 2025 |  |  | 2024 |
(in millions) |  |  |  |  |  |
Property Type: |  |  |  |  |  |
Office |  | $ | 116.1 |  |  | $ | 121.6 |
Apartments |  |  | 73.1 |  |  |  | 73.4 |
Hotel |  |  | 30.7 |  |  |  | 47.0 |
Industrial |  |  | 26.3 |  |  |  | 35.8 |
Retail |  |  | 8.9 |  |  |  | 32.8 |
Allowance for credit losses |  |  | (8.1 | ) |  |  | (5.7 | )
Total |  | $ | 247.0 |  |  | $ | 304.9 |
DECEMBER 31 |  | 2025 |  |  | 2024 |
(in millions) |  |  |  |  |  |
Geographic Region: |  |  |  |  |  |
South Atlantic |  | $ | 75.1 |  |  | $ | 82.2 |
Pacific |  |  | 63.5 |  |  |  | 82.7 |
New England |  |  | 39.7 |  |  |  | 40.6 |
Mid Atlantic |  |  | 28.7 |  |  |  | 42.6 |
West South Central |  |  | 22.3 |  |  |  | 22.8 |
West North Central |  |  | 8.9 |  |  |  | 9.1 |
Other |  |  | 16.9 |  |  |  | 30.6 |
Allowance for credit losses |  |  | (8.1 | ) |  |  | (5.7 | )
Total |  | $ | 247.0 |  |  | $ | 304.9 |
Schedule of Amortized Cost of Mortgage Loan Participations by Credit Ratings and Year of Origination | The amortized cost of mortgage loan participations by credit ratings and year of origination was as follows:
DECEMBER 31, 2025 |  |  |
(in millions) |  | Prior to 2021 |  |  | 2021 |  |  | 2022 |  |  | 2023 |  |  | 2024 |  |  | 2025 |  |  | Total |
Credit Quality |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aaa/Aa/A |  | $ | 87.0 |  |  | $ | 42.5 |  |  | $ | 10.0 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 139.5 |
Baa |  |  | 43.7 |  |  |  | 11.7 |  |  |  | — |  |  |  | — |  |  |  | 9.9 |  |  |  | 9.4 |  |  |  | 74.7 |
Ba and lower |  |  | 32.0 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 8.9 |  |  |  | — |  |  |  | 40.9 |
Amortized cost |  | $ | 162.7 |  |  | $ | 54.2 |  |  | $ | 10.0 |  |  | $ | — |  |  | $ | 18.8 |  |  | $ | 9.4 |  |  | $ | 255.1 |
Allowance for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (8.1 | )
Amortized cost, net of allowance for credit losses |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ | 247.0 |

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