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Investments - Net Investment Income and Equity in Earnings of Investees (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Net Investment Income |  |  |  |
Gross investment income | $ 82 | $ 90 | $ 167 | $ 172
Investment expenses | (1) | (1) | (2) | (2)
Net investment income | 81 | 89 | 165 | 170
Fair value gains (losses) on trading securities | 17 | 40 | 43 | 38
Equity in Earnings (Losses) of Investees | 5 | 5 | 29 | 7
Fair value gains (losses) on trading securities still held | 14 | 40 | 31 | 38
Externally managed |  |  |  |
Net Investment Income |  |  |  |
Gross investment income | 51 | 53 | 102 | 105
Loss Mitigation Securities |  |  |  |
Net Investment Income |  |  |  |
Gross investment income | 7 | 12 | 14 | 22
Puerto Rico, New Recovery Bonds |  |  |  |
Net Investment Income |  |  |  |
Gross investment income | 0 | 1 | 0 | 4
Other |  |  |  |
Net Investment Income |  |  |  |
Gross investment income | 2 | 4 | 6 | 7
Short-term investments |  |  |  |
Net Investment Income |  |  |  |
Gross investment income | 22 | 18 | 45 | 32
Other |  |  |  |
Net Investment Income |  |  |  |
Gross investment income | 0 | 2 | 0 | 2
Sound Point |  |  |  |
Net Investment Income |  |  |  |
Equity in Earnings (Losses) of Investees | (3) | 0 | 1 | 0
Funds |  |  |  |
Net Investment Income |  |  |  |
Equity in Earnings (Losses) of Investees | 5 | 0 | 19 | 0
Equity method investments |  |  |  |
Net Investment Income |  |  |  |
Equity in Earnings (Losses) of Investees | $ 3 | $ 5 | $ 9 | $ 7

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- Definition Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-14 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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