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Investments - Gross unrealized losses on securities by investment category and length of time that have been in a continuous unrealized loss position (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Fixed maturities |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (25) | $ (7)
Fair value - less than twelve months | $ 1,778 | $ 428
Fair value as percentage of cost - less than twelve months | 99.00% | 98.00%
Unrealized loss - twelve months or more | $ (328) | $ (463)
Fair value - twelve months or more | $ 4,156 | $ 5,999
Fair value as a percentage of cost - twelve months or more | 93.00% | 93.00%
U.S. Government and government agencies |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ 0 | $ 0
Fair value - less than twelve months | $ 35 | $ 11
Fair value as percentage of cost - less than twelve months | 100.00% | 100.00%
Unrealized loss - twelve months or more | $ (3) | $ (8)
Fair value - twelve months or more | $ 105 | $ 191
Fair value as a percentage of cost - twelve months or more | 97.00% | 96.00%
States, municipalities and political subdivisions |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (5) | $ (1)
Fair value - less than twelve months | $ 256 | $ 76
Fair value as percentage of cost - less than twelve months | 98.00% | 99.00%
Unrealized loss - twelve months or more | $ (44) | $ (37)
Fair value - twelve months or more | $ 470 | $ 526
Fair value as a percentage of cost - twelve months or more | 91.00% | 93.00%
Foreign government |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ 0 | $ 0
Fair value - less than twelve months | $ 98 | $ 0
Fair value as percentage of cost - less than twelve months | 100.00% | 0.00%
Unrealized loss - twelve months or more | $ (1) | $ (7)
Fair value - twelve months or more | $ 50 | $ 207
Fair value as a percentage of cost - twelve months or more | 98.00% | 97.00%
Residential MBS |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (6) | $ (1)
Fair value - less than twelve months | $ 452 | $ 42
Fair value as percentage of cost - less than twelve months | 99.00% | 98.00%
Unrealized loss - twelve months or more | $ (148) | $ (154)
Fair value - twelve months or more | $ 916 | $ 1,089
Fair value as a percentage of cost - twelve months or more | 86.00% | 88.00%
Commercial MBS |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ 0 | $ 0
Fair value - less than twelve months | $ 14 | $ 0
Fair value as percentage of cost - less than twelve months | 100.00% | 0.00%
Unrealized loss - twelve months or more | $ 0 | $ (1)
Fair value - twelve months or more | $ 16 | $ 61
Fair value as a percentage of cost - twelve months or more | 100.00% | 98.00%
Collateralized loan obligations |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ 0 | $ 0
Fair value - less than twelve months | $ 0 | $ 25
Fair value as percentage of cost - less than twelve months | 0.00% | 100.00%
Unrealized loss - twelve months or more | $ (12) | $ (28)
Fair value - twelve months or more | $ 247 | $ 807
Fair value as a percentage of cost - twelve months or more | 95.00% | 97.00%
Other asset-backed securities |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (4) | $ (1)
Fair value - less than twelve months | $ 318 | $ 151
Fair value as percentage of cost - less than twelve months | 99.00% | 99.00%
Unrealized loss - twelve months or more | $ (65) | $ (119)
Fair value - twelve months or more | $ 1,201 | $ 1,663
Fair value as a percentage of cost - twelve months or more | 95.00% | 93.00%
Corporate and other |  |
Available-for-sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (10) | $ (4)
Fair value - less than twelve months | $ 605 | $ 123
Fair value as percentage of cost - less than twelve months | 98.00% | 97.00%
Unrealized loss - twelve months or more | $ (55) | $ (109)
Fair value - twelve months or more | $ 1,151 | $ 1,455
Fair value as a percentage of cost - twelve months or more | 95.00% | 93.00%

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