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v3.23.2

Investments - Schedule of Fixed Maturities (Details) - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | $ 7,761.7 |  |  |
Gross unrealized gains | 46.4 |  |  |
Gross unrealized loss | (857.2) |  |  |
Fixed maturities, allowance for credit losses | (7.1) | $ (9.6) | $ 13.6 | $ 7.5
Fixed maturities at fair value | 6,943.8 |  |  |
Investments in Fixed Maturities |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost |  | 7,811.8 |  |
Gross unrealized gains |  | 29.4 |  |
Gross unrealized loss |  | (936.8) |  |
Fixed maturities at fair value |  | 6,894.8 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 857.2 | 936.8 |  |
Investments in Fixed Maturities | Investment-grade |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 827.1 | 904.0 |  |
U.S. Government and Government Agencies and Authorities |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 627.8 | 612.5 |  |
Gross unrealized gains | 1.4 | 1.3 |  |
Gross unrealized loss | (83.7) | (85.8) |  |
Fixed maturities, allowance for credit losses | 0.0 | 0.0 |  |
Fixed maturities at fair value | 545.5 | 528.0 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 83.7 | 85.8 |  |
States and Political Subdivisions |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 1,646.8 | 1,797.6 |  |
Gross unrealized gains | 21.9 | 10.3 |  |
Gross unrealized loss | (207.3) | (238.3) |  |
Fixed maturities, allowance for credit losses | (0.4) | (0.7) |  |
Fixed maturities at fair value | 1,461.0 | 1,568.9 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 207.3 | 238.3 |  |
Foreign Governments |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 4.8 | 5.0 |  |
Gross unrealized gains | 0.0 | 0.0 |  |
Gross unrealized loss | (0.8) | (0.9) |  |
Fixed maturities, allowance for credit losses | 0.0 | 0.0 |  |
Fixed maturities at fair value | 4.0 | 4.1 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 0.8 | 0.9 |  |
Corporate Debt Securities [Member] |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 4,083.2 | 4,030.3 |  |
Gross unrealized gains | 22.5 | 17.7 |  |
Gross unrealized loss | (465.6) | (499.7) |  |
Fixed maturities, allowance for credit losses | (6.7) | (8.9) | 13.6 | $ 7.5
Fixed maturities at fair value | 3,633.4 | 3,539.4 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 465.6 | 499.7 |  |
Redeemable Preferred Stocks |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 9.0 | 9.0 |  |
Gross unrealized gains | 0.0 | 0.0 |  |
Gross unrealized loss | (1.1) | (1.0) |  |
Fixed maturities, allowance for credit losses | 0.0 | 0.0 |  |
Fixed maturities at fair value | 7.9 | 8.0 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 1.1 |  | $ 1.0 |
Collateralized Loan Obligations |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 1,032.7 | 1,014.7 |  |
Gross unrealized gains | 0.4 | 0.0 |  |
Gross unrealized loss | (45.9) | (60.8) |  |
Fixed maturities, allowance for credit losses | 0.0 | 0.0 |  |
Fixed maturities at fair value | 987.2 | 953.9 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | 45.9 | 60.8 |  |
Other Mortgage- and Asset-backed |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Fixed maturities, at amortized cost | 357.4 | 342.7 |  |
Gross unrealized gains | 0.2 | 0.1 |  |
Gross unrealized loss | (52.8) | (50.3) |  |
Fixed maturities, allowance for credit losses | 0.0 | 0.0 |  |
Fixed maturities at fair value | 304.8 | 292.5 |  |
Debt securities, available-for-sale, unrealized loss position, accumulated loss | $ 52.8 | $ 50.3 |  |

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