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Investments and Cash - Gross Unrealized Loss by Length of Time (Details) $ in Millions | Dec. 31, 2022 USD ($) Security | Dec. 31, 2021 USD ($) Security
--- | --- | ---
Less than 12 months |  |
Fair Value | $ 3,751 | $ 804
Gross Unrealized Loss | (213) | (17)
12 months or more |  |
Fair Value | 1,017 | 120
Gross Unrealized Loss | (239) | (9)
Total |  |
Fair Value | 4,768 | 924
Gross Unrealized Loss | $ (452) | $ (26)
Number of securities |  |
Less than 12 months (in securities) | Security | 1,340 | 355
12 months or more (in securities) | Security | 466 | 60
Total (in securities) | Security | 1,776 | 410
Obligations of state and political subdivisions |  |
Less than 12 months |  |
Fair Value | $ 1,763 | $ 117
Gross Unrealized Loss | (79) | (3)
12 months or more |  |
Fair Value | 163 | 10
Gross Unrealized Loss | (56) | (1)
Total |  |
Fair Value | 1,926 | 127
Gross Unrealized Loss | (135) | (4)
U.S. government and agencies |  |
Less than 12 months |  |
Fair Value | 32 | 26
Gross Unrealized Loss | 0 | 0
12 months or more |  |
Fair Value | 52 | 32
Gross Unrealized Loss | (8) | (2)
Total |  |
Fair Value | 84 | 58
Gross Unrealized Loss | (8) | (2)
Corporate securities |  |
Less than 12 months |  |
Fair Value | 1,276 | 407
Gross Unrealized Loss | (95) | (12)
12 months or more |  |
Fair Value | 519 | 70
Gross Unrealized Loss | (147) | (5)
Total |  |
Fair Value | 1,795 | 477
Gross Unrealized Loss | (242) | (17)
RMBS |  |
Less than 12 months |  |
Fair Value | 147 | 4
Gross Unrealized Loss | (9) | 0
12 months or more |  |
Fair Value | 3 | 0
Gross Unrealized Loss | (1) | 0
Total |  |
Fair Value | 150 | 4
Gross Unrealized Loss | (10) | 0
CMBS |  |
Less than 12 months |  |
Fair Value | 270 |
Gross Unrealized Loss | (11) |
12 months or more |  |
Fair Value | 0 |
Gross Unrealized Loss | 0 |
Total |  |
Fair Value | 270 |
Gross Unrealized Loss | (11) |
CLOs |  |
Less than 12 months |  |
Fair Value | 171 | 226
Gross Unrealized Loss | (7) | 0
12 months or more |  |
Fair Value | 250 | 0
Gross Unrealized Loss | (14) | 0
Total |  |
Fair Value | 421 | 226
Gross Unrealized Loss | (21) | 0
Others |  |
Less than 12 months |  |
Fair Value | 27 |
Gross Unrealized Loss | (2) |
12 months or more |  |
Fair Value | 0 |
Gross Unrealized Loss | 0 |
Total |  |
Fair Value | 27 |
Gross Unrealized Loss | (2) |
Non-U.S. government securities |  |
Less than 12 months |  |
Fair Value | 65 | 24
Gross Unrealized Loss | (10) | (2)
12 months or more |  |
Fair Value | 30 | 8
Gross Unrealized Loss | (13) | (1)
Total |  |
Fair Value | 95 | 32
Gross Unrealized Loss | $ (23) | $ (3)

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