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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 | Mar. 31, 2025 | Dec. 31, 2024
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Total fixed maturities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (17) | $ (25)
Fair value - less than twelve months | $ 1,474 | $ 1,778
Fair value as percentage of cost - less than twelve months | 99.00% | 99.00%
Unrealized Loss - twelve months or more | $ (284) | $ (328)
Fair Value - twelve months or more | $ 3,895 | $ 4,156
Fair value as 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 | $ 20 | $ 35
Fair value as percentage of cost - less than twelve months | 100.00% | 100.00%
Unrealized Loss - twelve months or more | $ (3) | $ (3)
Fair Value - twelve months or more | $ 90 | $ 105
Fair value as percentage of cost - twelve months or more | 97.00% | 97.00%
States, municipalities and political subdivisions |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (5) | $ (5)
Fair value - less than twelve months | $ 158 | $ 256
Fair value as percentage of cost - less than twelve months | 97.00% | 98.00%
Unrealized Loss - twelve months or more | $ (46) | $ (44)
Fair Value - twelve months or more | $ 479 | $ 470
Fair value as percentage of cost - twelve months or more | 91.00% | 91.00%
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 | $ 2 | $ 98
Fair value as percentage of cost - less than twelve months | 100.00% | 100.00%
Unrealized Loss - twelve months or more | $ 0 | $ (1)
Fair Value - twelve months or more | $ 51 | $ 50
Fair value as percentage of cost - twelve months or more | 100.00% | 98.00%
Residential MBS |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (2) | $ (6)
Fair value - less than twelve months | $ 285 | $ 452
Fair value as percentage of cost - less than twelve months | 99.00% | 99.00%
Unrealized Loss - twelve months or more | $ (131) | $ (148)
Fair Value - twelve months or more | $ 920 | $ 916
Fair value as percentage of cost - twelve months or more | 88.00% | 86.00%
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 | $ 9 | $ 14
Fair value as percentage of cost - less than twelve months | 100.00% | 100.00%
Unrealized Loss - twelve months or more | $ 0 | $ 0
Fair Value - twelve months or more | $ 8 | $ 16
Fair value as percentage of cost - twelve months or more | 100.00% | 100.00%
Collateralized loan obligations |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (1) | $ 0
Fair value - less than twelve months | $ 292 | $ 0
Fair value as percentage of cost - less than twelve months | 100.00% | 0.00%
Unrealized Loss - twelve months or more | $ (10) | $ (12)
Fair Value - twelve months or more | $ 243 | $ 247
Fair value as percentage of cost - twelve months or more | 96.00% | 95.00%
Other asset-backed securities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (3) | $ (4)
Fair value - less than twelve months | $ 323 | $ 318
Fair value as percentage of cost - less than twelve months | 99.00% | 99.00%
Unrealized Loss - twelve months or more | $ (52) | $ (65)
Fair Value - twelve months or more | $ 1,034 | $ 1,201
Fair value as percentage of cost - twelve months or more | 95.00% | 95.00%
Corporate and other |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (6) | $ (10)
Fair value - less than twelve months | $ 385 | $ 605
Fair value as percentage of cost - less than twelve months | 98.00% | 98.00%
Unrealized Loss - twelve months or more | $ (42) | $ (55)
Fair Value - twelve months or more | $ 1,070 | $ 1,151
Fair value as percentage of cost - twelve months or more | 96.00% | 95.00%

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