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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, 2023 | Dec. 31, 2022
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Total fixed maturities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (106) | $ (425)
Fair value - less than twelve months | $ 3,184 | $ 6,540
Fair value as percentage of cost - Less than twelve months | 97.00% | 94.00%
Unrealized Loss - Twelve months or more | $ (471) | $ (244)
Fair Value - Twelve months or more | $ 4,908 | $ 2,344
Fair value as percentage of cost - Twelve months or more | 91.00% | 91.00%
U.S. government and government agencies |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (1) | $ (4)
Fair value - less than twelve months | $ 43 | $ 111
Fair value as percentage of cost - Less than twelve months | 98.00% | 97.00%
Unrealized Loss - Twelve months or more | $ (10) | $ (10)
Fair Value - Twelve months or more | $ 173 | $ 107
Fair value as percentage of cost - Twelve months or more | 95.00% | 91.00%
States, municipalities and political subdivisions |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (17) | $ (50)
Fair value - less than twelve months | $ 468 | $ 967
Fair value as percentage of cost - Less than twelve months | 96.00% | 95.00%
Unrealized Loss - Twelve months or more | $ (18) | $ (1)
Fair Value - Twelve months or more | $ 240 | $ 15
Fair value as percentage of cost - Twelve months or more | 93.00% | 94.00%
Foreign government |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (2) | $ (5)
Fair value - less than twelve months | $ 14 | $ 90
Fair value as percentage of cost - Less than twelve months | 88.00% | 95.00%
Unrealized Loss - Twelve months or more | $ (10) | $ (9)
Fair Value - Twelve months or more | $ 209 | $ 134
Fair value as percentage of cost - Twelve months or more | 95.00% | 94.00%
Residential MBS |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (18) | $ (115)
Fair value - less than twelve months | $ 397 | $ 1,078
Fair value as percentage of cost - Less than twelve months | 96.00% | 90.00%
Unrealized Loss - Twelve months or more | $ (157) | $ (65)
Fair Value - Twelve months or more | $ 939 | $ 315
Fair value as percentage of cost - Twelve months or more | 86.00% | 83.00%
Commercial MBS |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ 0 | $ (2)
Fair value - less than twelve months | $ 20 | $ 44
Fair value as percentage of cost - Less than twelve months | 100.00% | 96.00%
Unrealized Loss - Twelve months or more | $ (2) | $ (1)
Fair Value - Twelve months or more | $ 49 | $ 33
Fair value as percentage of cost - Twelve months or more | 96.00% | 97.00%
Collateralized loan obligations |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (12) | $ (44)
Fair value - less than twelve months | $ 697 | $ 1,224
Fair value as percentage of cost - Less than twelve months | 98.00% | 97.00%
Unrealized Loss - Twelve months or more | $ (41) | $ (23)
Fair Value - Twelve months or more | $ 908 | $ 587
Fair value as percentage of cost - Twelve months or more | 96.00% | 96.00%
Other asset-backed securities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (17) | $ (100)
Fair value - less than twelve months | $ 600 | $ 1,361
Fair value as percentage of cost - Less than twelve months | 97.00% | 93.00%
Unrealized Loss - Twelve months or more | $ (131) | $ (84)
Fair Value - Twelve months or more | $ 1,457 | $ 740
Fair value as percentage of cost - Twelve months or more | 92.00% | 90.00%
Corporate and other |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (39) | $ (105)
Fair value - less than twelve months | $ 945 | $ 1,665
Fair value as percentage of cost - Less than twelve months | 96.00% | 94.00%
Unrealized Loss - Twelve months or more | $ (102) | $ (51)
Fair Value - Twelve months or more | $ 933 | $ 413
Fair value as percentage of cost - Twelve months or more | 90.00% | 89.00%

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