Investments (Schedule Of Amortized Cost And Fair Value Of Held-to-Maturity Fixed Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity	$ 8,458	$ 8,882
Debt Securities, Held to maturity, Allowance for Credit Loss	33	34	$ 34	$ 35
Debt securities, held to maturity, net carrying value	8,425	8,848
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	8	3
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss	(324)	(412)
Held to maturity, Fair Value	8,109	8,439
U.S. Treasury / Agency
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity	1,371	1,417
Debt Securities, Held to maturity, Allowance for Credit Loss	0	0
Debt securities, held to maturity, net carrying value	1,371	1,417
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	4	1
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss	(35)	(48)
Held to maturity, Fair Value	1,340	1,370
Non-U.S.
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity	1,110	1,140
Debt Securities, Held to maturity, Allowance for Credit Loss	4	4
Debt securities, held to maturity, net carrying value	1,106	1,136
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss	(70)	(82)
Held to maturity, Fair Value	1,036	1,054
Corporate and asset-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity	1,699	1,733
Debt Securities, Held to maturity, Allowance for Credit Loss	28	28
Debt securities, held to maturity, net carrying value	1,671	1,705
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	2	1
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss	(97)	(126)
Held to maturity, Fair Value	1,576	1,580
Mortgage-backed securities
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity	1,373	1,456
Debt Securities, Held to maturity, Allowance for Credit Loss	1	1
Debt securities, held to maturity, net carrying value	1,372	1,455
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss	(90)	(104)
Held to maturity, Fair Value	1,282	1,351
Municipal
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity	2,905	3,136
Debt Securities, Held to maturity, Allowance for Credit Loss	0	1
Debt securities, held to maturity, net carrying value	2,905	3,135
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	2	1
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss	(32)	(52)
Held to maturity, Fair Value	$ 2,875	$ 3,084

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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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