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v3.25.3

Fair Value Measurements - Level 3 Inputs Reconciliation (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | $ 346,200,000 | $ 246,700,000 | $ 209,000,000.0 | $ 192,300,000
Included in Condensed Consolidated Statement of Operations | (1,500,000) | 100,000 | 1,900,000 | 1,800,000
Included in Other Comprehensive Income (Loss) | (3,600,000) | 2,000,000.0 | (1,000,000.0) | 2,000,000.0
Purchases | 110,900,000 | 30,900,000 | 368,100,000 | 112,700,000
Sales | (65,400,000) | (31,800,000) | (147,700,000) | (49,800,000)
Transfers into Level 3 | 1,700,000 | 5,700,000 | 16,700,000 | 10,500,000
Transfers out of Level 3 | (54,300,000) | (8,700,000) | (113,000,000.0) | (24,600,000)
Balance, End of Period | 334,000,000.0 | 244,900,000 | 334,000,000.0 | 244,900,000
Corporate Bonds and Notes |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 261,600,000 | 227,300,000 | 194,200,000 | 177,100,000
Included in Condensed Consolidated Statement of Operations | 400,000 | 300,000 | 1,900,000 | 200,000
Included in Other Comprehensive Income (Loss) | (4,800,000) | 1,700,000 | (2,100,000) | 2,300,000
Purchases | 87,600,000 | 30,900,000 | 216,500,000 | 103,500,000
Sales | (64,100,000) | (31,800,000) | (134,600,000) | (48,100,000)
Transfers into Level 3 | 0 | 3,900,000 | 5,000,000.0 | 7,000,000.0
Transfers out of Level 3 | 0 | (1,900,000) | (200,000) | (11,600,000)
Balance, End of Period | 280,700,000 | 230,400,000 | 280,700,000 | 230,400,000
Foreign Governments |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 0 |  | 0 |
Included in Condensed Consolidated Statement of Operations | 0 |  | 0 |
Included in Other Comprehensive Income (Loss) | 0 |  | 0 |
Purchases | 5,000,000.0 |  | 5,000,000.0 |
Sales | (2,500,000) |  | (2,500,000) |
Transfers into Level 3 | 0 |  | 0 |
Transfers out of Level 3 | 0 |  | 0 |
Balance, End of Period | 2,500,000 |  | 2,500,000 |
States and Political Subdivisions |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 200,000 | 100,000 | 1,800,000 | 100,000
Included in Condensed Consolidated Statement of Operations | 0 | 0 | 0 | 0
Included in Other Comprehensive Income (Loss) | (100,000) | (200,000) | (200,000) | (600,000)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Transfers into Level 3 | 1,700,000 | 1,800,000 | 1,700,000 | 3,500,000
Transfers out of Level 3 | 0 | 0 | (1,500,000) | (1,300,000)
Balance, End of Period | 1,800,000 | 1,700,000 | 1,800,000 | 1,700,000
Redeemable Preferred Stocks |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 4,300,000 | 4,100,000 | 4,200,000 | 7,100,000
Included in Condensed Consolidated Statement of Operations | 0 | 0 | 0 | 0
Included in Other Comprehensive Income (Loss) | 100,000 | 200,000 | 200,000 | 200,000
Purchases | 0 | 0 | 0 | 1,900,000
Sales | 0 | 0 | 0 | 0
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | 0 | 0 | 0 | (4,900,000)
Balance, End of Period | 4,400,000 | 4,300,000 | 4,400,000 | 4,300,000
Collateralized Loan Obligations |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 52,800,000 | 6,800,000 | 0 | 0
Included in Condensed Consolidated Statement of Operations | 0 | 0 | 0 | 0
Included in Other Comprehensive Income (Loss) | 0 | 0 | 0 | 0
Purchases | 5,700,000 | 0 | 125,500,000 | 6,800,000
Sales | 0 | 0 | (10,000,000.0) | 0
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | (52,800,000) | (6,800,000) | (109,800,000) | (6,800,000)
Balance, End of Period | 5,700,000 | 0 | 5,700,000 | 0
Other Mortgage- and Asset-backed |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 22,500,000 | 5,000,000.0 | 5,000,000.0 | 5,200,000
Included in Condensed Consolidated Statement of Operations | 0 | 0 | 0 | 0
Included in Other Comprehensive Income (Loss) | 800,000 | 300,000 | 700,000 | 100,000
Purchases | 13,100,000 | 0 | 20,800,000 | 0
Sales | 0 | 0 | (100,000) | 0
Transfers into Level 3 | 0 | 0 | 10,000,000.0 | 0
Transfers out of Level 3 | (1,500,000) | 0 | (1,500,000) | 0
Balance, End of Period | 34,900,000 | 5,300,000 | 34,900,000 | 5,300,000
Equity Securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning of Period | 4,800,000 | 3,400,000 | 3,800,000 | 2,800,000
Included in Condensed Consolidated Statement of Operations | (1,900,000) | (200,000) | 0 | 1,600,000
Included in Other Comprehensive Income (Loss) | 400,000 | 0 | 400,000 | 0
Purchases | (500,000) | 0 | 300,000 | 500,000
Sales | 1,200,000 | 0 | (500,000) | (1,700,000)
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | 0 | 0 | 0 | 0
Balance, End of Period | $ 4,000,000.0 | $ 3,200,000 | $ 4,000,000.0 | $ 3,200,000

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