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Investments (Allowance on available-for-sale securities with credit impairments and PCD assets activity) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Allowance for credit losses: |  |
Balance, beginning of period | $ 16 | $ 1
Additions to the allowance for credit losses: |  |
Securities for which credit losses were not previously recorded | 27 | 17
Available-for-sale securities accounted for as PCD assets | 4 | 22
Reductions to the allowance for credit losses: |  |
Securities sold during the period (realized) | 4 | 6
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis | 1 | 8
Write-offs charged against the allowance | 9 | 15
Recoveries of amounts previously written off | 0 | 0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period | 12 | 5
Balance, end of period | 45 | 16
Corporate and other bonds |  |
Allowance for credit losses: |  |
Balance, beginning of period | 4 | 0
Additions to the allowance for credit losses: |  |
Securities for which credit losses were not previously recorded | 9 | 10
Available-for-sale securities accounted for as PCD assets | 4 | 22
Reductions to the allowance for credit losses: |  |
Securities sold during the period (realized) | 3 | 6
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis | 1 | 8
Write-offs charged against the allowance | 0 | 15
Recoveries of amounts previously written off | 0 | 0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period | 0 | 1
Balance, end of period | 13 | 4
Asset-backed |  |
Allowance for credit losses: |  |
Balance, beginning of period | 12 | 1
Additions to the allowance for credit losses: |  |
Securities for which credit losses were not previously recorded | 18 | 7
Available-for-sale securities accounted for as PCD assets | 0 | 0
Reductions to the allowance for credit losses: |  |
Securities sold during the period (realized) | 1 | 0
Intent to sell or more likely than not will be required to sell the security before recovery of its amortized cost basis | 0 | 0
Write-offs charged against the allowance | 9 | 0
Recoveries of amounts previously written off | 0 | 0
Additional increases or (decreases) to the allowance for credit losses on securities that had an allowance recorded in a previous period | 12 | 4
Balance, end of period | $ 32 | $ 12

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- Definition Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-9 + Details
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