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Investments - Realized Investment Gains and Losses and Change in Unrealized Investment Gains and Losses and Other Items (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Investment income: |  |  |  |
Interest | $ 227 | $ 187 | $ 651 | $ 529
Dividends | 69 | 68 | 206 | 209
Other | 4 | 7 | 16 | 18
Total | 300 | 262 | 873 | 756
Less investment expenses | 5 | 4 | 13 | 11
Total | 295 | 258 | 860 | 745
Investment gains and losses, net |  |  |  |
Other | 6 | 3 | 18 | 29
Total | 853 | 758 | 1,259 | 1,507
Equity securities |  |  |  |
Investment gains and losses, net |  |  |  |
Investment gains and losses on securities sold, net | (9) | 24 | (5) | 146
Unrealized gains and losses on securities still held, net | 855 | 817 | 1,259 | 1,446
Total | 846 | 841 | 1,254 | 1,592
Fixed maturities |  |  |  |
Investment gains and losses, net |  |  |  |
Gross realized gains | 2 | 1 | 3 | 5
Gross realized losses | (1) | (87) | (1) | (94)
Change in allowance for credit losses, net | 0 | 0 | (15) | (25)
Total | $ 1 | $ (86) | $ (13) | $ (114)

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- Definition This item represents realized investment gains (losses) included in earnings for the period excluding those relating to other than temporary impairment losses on investments in debt securities. Includes realized investment gains and losses generated from the sale of debt securities, equity securities, investments in joint ventures and limited partnerships and from other than temporary impairments on investments other than debt securities. Also includes realized investment gains and losses are generated from prepayment premiums, recoveries of principal on previously impaired securities, provisions for losses on commercial mortgage and other loans, and fair value changes on embedded derivatives and derivatives that do not qualify for hedge accounting treatment, except those derivatives used in the Company's capacity as a broker or dealer. + References No definition available. + Details
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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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- Definition Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-9 + Details
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- Definition Amount, before 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/1943274/2147479168/946-830-55-10 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)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1 + Details
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