Investments (Schedule Of Fixed Maturities By Contractual Maturity) (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost		$ 72,229
Available for sale, Mortgage-backed securities, Amortized Cost		18,470
Available for sale, Due in 1 year or less, Fair Value	$ 4,498	4,760
Available for sale, Due after 1 year through 5 years, Fair Value	25,542	26,227
Available for sale, Due after 5 years through 10 years, Fair Value	28,207	27,232
Available for sale, Due after 10 years, Fair Value	14,372	14,010
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value	72,619	72,229
Available for sale, Mortgage backed securities, Fair Value	20,489	18,470
Available for sale, Fair Value	93,108	90,699
Debt securities, Held-to-maturity, maturity, allocated and single maturity date, within on year, net carrying value	888	1,231
Debt securities, Held-to-maturity, maturity, allocated and single maturity date, after one through five years, net carrying value	3,744	3,592
Debt securities, Held-to-maturity, maturity, allocated and single maturity date, after five through ten years, net carrying value	2,242	3,029
Debt securities, Held-to-maturity, maturity, allocated and single maturity date, after 10 years, net carrying value	1,514	1,802
Debt securities, Held-to-maturity, maturity, allocated and single maturity date, net carrying value	8,388	9,654
Debt securities, Held-to-maturity, without single maturity date, net carrying value	1,730	1,999
Held to maturity, Due in 1 year or less, Fair Value	894	1,240
Held to maturity, Due after 1 year through 5, Fair Value	3,846	3,760
Held to maturity, Due after 5 years through 10 years, Fair Value	2,349	3,228
Held to maturity, Due after 10 years, Fair Value	1,755	2,136
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Fair Value	8,844	10,364
Held to maturity, Mortgage backed securities, Fair Value	1,803	2,146
Fixed maturities held to maturity, at amortized cost, net of valuation allowance - $35 and $44 (fair value – $10,647 and $12,510)	10,118	11,653
Held to maturity, Fair Value	$ 10,647	$ 12,510