Investments (Available-For-Sale Securities By Contractual Maturities) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Available-for-sale Securities, Debt Maturities, Amortized Cost
Amortized Cost, Total	$ 110,681	$ 110,944
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	103,119	$ 99,465
Fixed Maturity AFS Securities Excluding Structured Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Due in one year or less	3,523
Due after one year through five years	18,371
Due after five years through ten years	18,548
Due after ten years	53,720
Amortized Cost, Total	94,162
Available-for-sale Securities, Debt Maturities, Fair Value
Due in one year or less	3,481
Due after one year through five years	17,485
Due after five years through ten years	17,136
Due after ten years	49,592
Available-for-sale Securities, Debt Securities, Total	87,694
Structured Securities [Member]
Available-for-sale Securities, Debt Maturities, Amortized Cost
Amortized Cost, Total	16,519
Available-for-sale Securities, Debt Maturities, Fair Value
Available-for-sale Securities, Debt Securities, Total	$ 15,425

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
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-Publisher FASB
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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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