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Investments and Cash - Gross Unrealized Loss by Length of Time (Details) $ in Millions | Dec. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($) security
--- | --- | ---
Less than 12 months |  |
Fair Value | $ 1,975 | $ 766
Gross Unrealized Loss | (40) | (7)
12 months or more |  |
Fair Value | 2,417 | 3,162
Gross Unrealized Loss | (277) | (281)
Total |  |
Fair Value | 4,392 | 3,928
Gross Unrealized Loss | $ (317) | $ (288)
Number of securities |  |
Less than 12 months (in securities) | security | 569 | 274
12 months or more (in securities) | security | 1,065 | 1,266
Total (in securities) | security | 1,591 | 1,525
Obligations of state and political subdivisions |  |
Less than 12 months |  |
Fair Value | $ 624 | $ 641
Gross Unrealized Loss | (7) | (4)
12 months or more |  |
Fair Value | 964 | 931
Gross Unrealized Loss | (96) | (87)
Total |  |
Fair Value | 1,588 | 1,572
Gross Unrealized Loss | (103) | (91)
U.S. government and agencies |  |
Less than 12 months |  |
Fair Value | 5 | 0
Gross Unrealized Loss | 0 | 0
12 months or more |  |
Fair Value | 28 | 33
Gross Unrealized Loss | (6) | (6)
Total |  |
Fair Value | 33 | 33
Gross Unrealized Loss | (6) | (6)
Corporate securities |  |
Less than 12 months |  |
Fair Value | 762 | 72
Gross Unrealized Loss | (20) | (1)
12 months or more |  |
Fair Value | 1,046 | 1,426
Gross Unrealized Loss | (150) | (152)
Total |  |
Fair Value | 1,808 | 1,498
Gross Unrealized Loss | (170) | (153)
RMBS |  |
Less than 12 months |  |
Fair Value | 255 | 27
Gross Unrealized Loss | (4) | (1)
12 months or more |  |
Fair Value | 123 | 124
Gross Unrealized Loss | (10) | (8)
Total |  |
Fair Value | 378 | 151
Gross Unrealized Loss | (14) | (9)
CMBS |  |
Less than 12 months |  |
Fair Value | 83 | 3
Gross Unrealized Loss | 0 | 0
12 months or more |  |
Fair Value | 103 | 148
Gross Unrealized Loss | (3) | (6)
Total |  |
Fair Value | 186 | 151
Gross Unrealized Loss | (3) | (6)
CLOs |  |
Less than 12 months |  |
Fair Value | 151 | 22
Gross Unrealized Loss | (5) | (1)
12 months or more |  |
Fair Value | 107 | 379
Gross Unrealized Loss | (1) | (6)
Total |  |
Fair Value | 258 | 401
Gross Unrealized Loss | (6) | (7)
Others |  |
Less than 12 months |  |
Fair Value | 60 | 1
Gross Unrealized Loss | (1) | 0
12 months or more |  |
Fair Value | 16 | 26
Gross Unrealized Loss | 0 | (1)
Total |  |
Fair Value | 76 | 27
Gross Unrealized Loss | (1) | (1)
Non-U.S. government securities |  |
Less than 12 months |  |
Fair Value | 35 | 0
Gross Unrealized Loss | (3) | 0
12 months or more |  |
Fair Value | 30 | 95
Gross Unrealized Loss | (11) | (15)
Total |  |
Fair Value | 65 | 95
Gross Unrealized Loss | $ (14) | $ (15)

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