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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, 2024 | Dec. 31, 2023
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Total fixed maturities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (9) | $ (7)
Fair value - less than twelve months | $ 936 | $ 428
Fair value as percentage of cost - Less than twelve months | 99.00% | 98.00%
Unrealized Loss - Twelve months or more | $ (439) | $ (463)
Fair Value - Twelve months or more | $ 5,407 | $ 5,999
Fair value as percentage of cost - Twelve months or more | 92.00% | 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 | $ 27 | $ 11
Fair value as percentage of cost - Less than twelve months | 100.00% | 100.00%
Unrealized Loss - Twelve months or more | $ (7) | $ (8)
Fair Value - Twelve months or more | $ 150 | $ 191
Fair value as percentage of cost - Twelve months or more | 96.00% | 96.00%
States, municipalities and political subdivisions |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (2) | $ (1)
Fair value - less than twelve months | $ 184 | $ 76
Fair value as percentage of cost - Less than twelve months | 99.00% | 99.00%
Unrealized Loss - Twelve months or more | $ (43) | $ (37)
Fair Value - Twelve months or more | $ 529 | $ 526
Fair value as percentage of cost - Twelve months or more | 92.00% | 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 | $ 17 | $ 0
Fair value as percentage of cost - Less than twelve months | 100.00% | 0.00%
Unrealized Loss - Twelve months or more | $ (5) | $ (7)
Fair Value - Twelve months or more | $ 206 | $ 207
Fair value as 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 | $ (1) | $ (1)
Fair value - less than twelve months | $ 127 | $ 42
Fair value as percentage of cost - Less than twelve months | 99.00% | 98.00%
Unrealized Loss - Twelve months or more | $ (155) | $ (154)
Fair Value - Twelve months or more | $ 1,017 | $ 1,089
Fair value as percentage of cost - Twelve months or more | 87.00% | 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 | $ 0 | $ 0
Fair value as percentage of cost - Less than twelve months | 0.00% | 0.00%
Unrealized Loss - Twelve months or more | $ 0 | $ (1)
Fair Value - Twelve months or more | $ 42 | $ 61
Fair value as 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 | $ 70 | $ 25
Fair value as percentage of cost - Less than twelve months | 100.00% | 100.00%
Unrealized Loss - Twelve months or more | $ (22) | $ (28)
Fair Value - Twelve months or more | $ 456 | $ 807
Fair value as 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 | $ (1) | $ (1)
Fair value - less than twelve months | $ 103 | $ 151
Fair value as percentage of cost - Less than twelve months | 99.00% | 99.00%
Unrealized Loss - Twelve months or more | $ (101) | $ (119)
Fair Value - Twelve months or more | $ 1,591 | $ 1,663
Fair value as percentage of cost - Twelve months or more | 94.00% | 93.00%
Corporate and other |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (5) | $ (4)
Fair value - less than twelve months | $ 408 | $ 123
Fair value as percentage of cost - Less than twelve months | 99.00% | 97.00%
Unrealized Loss - Twelve months or more | $ (106) | $ (109)
Fair Value - Twelve months or more | $ 1,416 | $ 1,455
Fair value as percentage of cost - Twelve months or more | 93.00% | 93.00%

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