Investments (Aggregate Fair Value And Gross Unrealized Loss By Length Of Time Security Has Continuously Been In Unrealized Loss Position) (Details) - Fixed Maturities [Member] - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 30,498	$ 57,189
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(986)	(4,115)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	48,552	14,991
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(5,133)	(2,291)
Debt Securities, Available-for-sale, Unrealized Loss Position	79,050	72,180
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(6,119)	(6,406)
U.S. Treasury / Agency
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	1,843	2,152
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(70)	(125)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,779	386
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(134)	(46)
Debt Securities, Available-for-sale, Unrealized Loss Position	3,622	2,538
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(204)	(171)
Non-U.S.
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	7,895	15,538
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(243)	(1,012)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	14,825	5,490
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,377)	(704)
Debt Securities, Available-for-sale, Unrealized Loss Position	22,720	21,028
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(1,620)	(1,716)
Corporate and asset-backed securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	11,053	25,687
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(352)	(1,793)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	19,674	4,190
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,718)	(552)
Debt Securities, Available-for-sale, Unrealized Loss Position	30,727	29,877
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(2,070)	(2,345)
Mortgage-backed securities
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	6,081	10,561
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(258)	(1,033)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	11,418	4,770
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1,763)	(941)
Debt Securities, Available-for-sale, Unrealized Loss Position	17,499	15,331
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(2,021)	(1,974)
Municipal
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	3,626	3,251
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(63)	(152)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	856	155
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(141)	(48)
Debt Securities, Available-for-sale, Unrealized Loss Position	4,482	3,406
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (204)	$ (200)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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