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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 | Jun. 30, 2021 | Dec. 31, 2020
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Total fixed maturities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (6) | $ (14)
Fair value - less than twelve months | $ 936 | $ 952
Fair value as percentage of cost - Less than twelve months | 99.00% | 99.00%
Unrealized Loss - Twelve months or more | $ (6) | $ (7)
Fair Value - Twelve months or more | $ 409 | $ 497
Fair value as percentage of cost - Twelve months or more | 99.00% | 99.00%
U.S. Government and government agencies |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (1) | $ 0
Fair value - less than twelve months | $ 109 | $ 23
Fair value as percentage of cost - Less than twelve months | 99.00% | 100.00%
Unrealized Loss - Twelve months or more | $ 0 | $ 0
Fair Value - Twelve months or more | $ 0 | $ 0
Fair value as percentage of cost - Twelve months or more | 0.00% | 0.00%
States, municipalities and political subdivisions |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ 0 | $ 0
Fair value - less than twelve months | $ 6 | $ 39
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 | $ 17 | $ 10
Fair value as percentage of cost - Twelve months or more | 100.00% | 100.00%
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 | $ 35 | $ 7
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 | $ 0 | $ 0
Fair value as percentage of cost - Twelve months or more | 0.00% | 0.00%
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 | $ 82 | $ 86
Fair value as percentage of cost - Less than twelve months | 99.00% | 99.00%
Unrealized Loss - Twelve months or more | $ (1) | $ 0
Fair Value - Twelve months or more | $ 10 | $ 7
Fair value as percentage of cost - Twelve months or more | 91.00% | 100.00%
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 | $ 7
Fair value as percentage of cost - Less than twelve months | 0.00% | 100.00%
Unrealized Loss - Twelve months or more | $ 0 | $ 0
Fair Value - Twelve months or more | $ 0 | $ 5
Fair value as percentage of cost - Twelve months or more | 0.00% | 100.00%
Collateralized loan obligations |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (1) | $ (1)
Fair value - less than twelve months | $ 297 | $ 192
Fair value as percentage of cost - Less than twelve months | 100.00% | 99.00%
Unrealized Loss - Twelve months or more | $ (1) | $ (3)
Fair Value - Twelve months or more | $ 235 | $ 366
Fair value as percentage of cost - Twelve months or more | 100.00% | 99.00%
Other asset-backed securities |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (1) | $ (10)
Fair value - less than twelve months | $ 288 | $ 465
Fair value as percentage of cost - Less than twelve months | 100.00% | 98.00%
Unrealized Loss - Twelve months or more | $ (3) | $ (3)
Fair Value - Twelve months or more | $ 92 | $ 92
Fair value as percentage of cost - Twelve months or more | 97.00% | 97.00%
Corporate and other |  |
Available for sale securities in a continuous unrealized loss position |  |
Unrealized loss - less than twelve months | $ (2) | $ (2)
Fair value - less than twelve months | $ 119 | $ 133
Fair value as percentage of cost - Less than twelve months | 98.00% | 99.00%
Unrealized Loss - Twelve months or more | $ (1) | $ (1)
Fair Value - Twelve months or more | $ 55 | $ 17
Fair value as percentage of cost - Twelve months or more | 98.00% | 94.00%

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- Definition Available for sale securities continuous unrealized loss position twelve months or longer fair value as percentage of cost. + References No definition available. + Details
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