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Investments and Cash - Net Investment Income (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Net Investment Income |  |  |
Gross investment income | $ 370 | $ 274 | $ 275
Investment expenses | (5) | (5) | (6)
Net investment income | 365 | 269 | 269
Fair value gains (losses) on trading securities | 74 | (34) | 0
Equity in earnings (losses) of investees | 28 | (39) | 94
Fair value loss on trading securities still held | $ 31 | (29) |
Fair Value, Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Fair value gains (losses) on trading securities |  |
Externally managed |  |  |
Net Investment Income |  |  |
Gross investment income | $ 207 | 201 | 212
Loss Mitigation Securities |  |  |
Net Investment Income |  |  |
Gross investment income | 55 | 31 | 38
Puerto Rico, New Recovery Bonds |  |  |
Net Investment Income |  |  |
Gross investment income | 12 | 7 | 0
Other |  |  |
Net Investment Income |  |  |
Gross investment income | 20 | 19 | 24
Short-term investments |  |  |
Net Investment Income |  |  |
Gross investment income | 73 | 15 | 0
Other Investments |  |  |
Net Investment Income |  |  |
Gross investment income | 3 | 1 | 1
Sound Point |  |  |
Net Investment Income |  |  |
Equity in earnings (losses) of investees | 5 | 0 | 0
Equity Funds |  |  |
Net Investment Income |  |  |
Equity in earnings (losses) of investees | 15 | 2 | 30
Other |  |  |
Net Investment Income |  |  |
Equity in earnings (losses) of investees | $ 8 | $ (41) | $ 64

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- Definition Amount of unrealized gain (loss) recognized in income from asset (liability) measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480167/946-830-55-10 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(4)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 45 -Paragraph 5 -SubTopic 220 -Topic 946 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483581/946-220-45-5 + Details
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