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Investments (Narrative) (Details) - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2023 | Dec. 31, 2022
Investments [Line Items] |  |
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Transfer, Amount | $ 8,200,000,000 |
Debt Securities, Available-for-Sale and Held-to-Maturity, Fair Value | 7,800,000,000 |
Debt Securities, Held-to-Maturity, Transfer, Unrealized Gain (Loss) | 428,000,000 |
Restricted assets in fixed maturities and short-term investments | 17,505,000,000 | $ 15,721,000,000
Restricted assets in cash | 192,000,000 | $ 115,000,000
Investments |  |
Investments [Line Items] |  |
Deferred Tax Assets, Valuation Allowance | $ 1,108,000,000 |

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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity) and 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/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-5A Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) transferred to investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Subparagraph (a) -SubTopic 10 -Topic 320 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-10 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-2 + Details
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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482913/230-10-50-8 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-4 + Details
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