Investments (Available-For-Sale Securities By Contractual Maturities) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Available-for-sale Securities, Debt Maturities, Amortized Cost
Amortized Cost, Total	$ 110,943	$ 110,944
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	100,387	$ 99,465
Fixed Maturity AFS Securities Excluding Structured Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Due in one year or less	3,950
Due after one year through five years	18,900
Due after five years through ten years	18,279
Due after ten years	52,633
Amortized Cost, Total	93,762
Available-for-sale Securities, Debt Maturities, Fair Value
Due in one year or less	3,907
Due after one year through five years	17,925
Due after five years through ten years	16,548
Due after ten years	46,049
Available-for-sale Securities, Debt Securities, Total	84,429
Structured Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Amortized Cost, Total	17,181
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	$ 15,958

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: 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)(1))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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