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Investments (Rollforward of expected credit losses Private Debt HFI) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Private Debt, Held-for-investment, Allowance for Credit Loss [Line Items] |  |  |  |
Private Debt Held-for-investment, Allowance for Credit Loss, Beginning Balance | $ 3 | $ 5 | $ 4 | $ 4
Private Debt Held-for-investment, Allowance for Credit Loss, Period Increase (Decrease) | 1 | 0 | 1 | 2
Private Debt Held-for-investment, Allowance for Credit Loss, Recovery | (1) | 0 | (2) | (1)
Private Debt Held-for-investment, Allowance for Credit Loss, Ending Balance | $ 3 | $ 5 | $ 3 | $ 5

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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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- Definition Amount of increase in allowance for credit loss on financing receivable from recovery. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (c)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 + Details
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