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Segment Information - Supplemental Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | $ 403 | $ 344 | $ 494
Net investment income | 340 | 365 | 269
Loss and LAE (benefit) | (26) | 162 | 16
Amortization of DAC | 20 | 13 | 14
Other Expenses | 361 | 468 | 425
Operating segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 406 | 347 | 497
Net investment income | 339 | 370 | 278
Loss and LAE (benefit) | (18) | 161 | 12
Amortization of DAC | 20 | 13 | 14
Other Expenses | 293 | 338 | 350
Operating segments | Insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 406 | 347 | 497
Net investment income | 339 | 370 | 278
Loss and LAE (benefit) | (18) | 161 | 12
Amortization of DAC | 20 | 13 | 14
Other Expenses | 287 | 261 | 232
Non-cash compensation and operating expenses | 60 | 38 | 41
Operating segments | Asset Management |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 0 | 0 | 0
Net investment income | 0 | 0 | 0
Loss and LAE (benefit) | 0 | 0 | 0
Amortization of DAC | 0 | 0 | 0
Other Expenses | 6 | 77 | 118
Non-cash compensation and operating expenses | 0 | 8 | 18
Corporate division |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 0 | 0 | 0
Net investment income | 14 | 8 | 4
Loss and LAE (benefit) | 0 | 0 | 0
Amortization of DAC | 0 | 0 | 0
Other Expenses | 68 | 117 | 54
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | (3) | (3) | (3)
Net investment income | (13) | (13) | (13)
Loss and LAE (benefit) | (7) | 3 | 8
Amortization of DAC | 0 | 0 | 0
Other Expenses | 0 | 13 | 21
Subtotal |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 403 | 344 | 494
Net investment income | 340 | 365 | 269
Loss and LAE (benefit) | (25) | 164 | 20
Amortization of DAC | 20 | 13 | 14
Other Expenses | 361 | 468 | 425
Reconciling item |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 0 | 0 | 0
Net investment income | 0 | 0 | 0
Loss and LAE (benefit) | (1) | (2) | (4)
Amortization of DAC | 0 | 0 | 0
Other Expenses | $ 0 | $ 0 | $ 0

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