Accumulated Other Comprehensive Loss (Reconciliation Of The Components Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Accumulated Other Comprehensive Loss, Beginning Balance	$ (2,050)	$ (2,490)	$ (1,246)	$ (197)	$ (2,490)	$ (197)
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax	(119)		(922)		308	(1,991)
Other comprehensive loss (income) attributable to noncontrolling interests	0		3		(2)	8
Other Comprehensive Income (Loss), Tax, Portion Attributable to Noncontrolling Interest	0		(1)		0	(3)
Cash flow hedges, holding gain (loss), net of tax	4		3		15	6
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	3		9		5	16
Change in future policy benefits, net of tax	(3)		8		(1)	17
Foreign currency translation adjustment, net of tax	0		(5)		2	(8)
Other Comprehensive Income (Loss), Net of Tax	(116)	442	(908)	(1,054)	326	(1,962)
Accumulated Other Comprehensive Loss, Ending Balance	(2,166)	(2,050)	(2,151)	(1,246)	(2,166)	(2,151)
Other Comprehensive Income (Loss), Tax (Expense) Benefit, Portion Attributable to Parent	32		285		(72)	617
Net unrealized investment (losses) gains
AOCI, Debt Securities, Beginning Balance	(1,330)	(1,755)	(570)	494	(1,755)	494
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax	(191)		(1,050)		146	(2,196)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	72		128		162	205
OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax	(119)		(922)		308	(1,991)
Other comprehensive loss (income) attributable to noncontrolling interests	0		3		(2)	8
AOCI, Debt Securities, Ending Balance	(1,449)	(1,330)	(1,489)	(570)	(1,449)	(1,489)
Net holding gain (loss) on investment securities arising during the period, tax (expense) benefit	61		323		(25)	677
Reclassification adjustment for net realized loss (gain) on investment securities, tax (benefit) expense	(23)		(34)		(51)	(55)
Non-credit components of impairments on investments [Member]
AOCI, Other than Temporary Impairment, Not Credit Loss, Beginning Balance	(5)	(3)	(1)	0	(3)	0
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Loss, Net of Tax, Including Portion Attributable to Noncontrolling Interest, Available-for-sale Securities	(1)		(1)		(3)	(2)
AOCI, Other than Temporary Impairment, Not Credit Loss, Ending Balance	(6)	(5)	(2)	(1)	(6)	(2)
Tax (expense) benefit of non credit impairment on available-for-sale securities recognized in other comprehensive income (loss)	0		0		1	1
Net cash flow hedges
AOCI, Cash Flow Hedge, Beginning Balance	(218)	(229)	(236)	(239)	(229)	(239)
Cash flow hedges, holding gain (loss), net of tax	4		3		15	6
AOCI, Cash Flow Hedge, Ending Balance	(214)	(218)	(233)	(236)	(214)	(233)
Cash flow hedges, holding gain (loss), tax (expense) benefit	(1)		(1)		7	(2)
Pension and other postretirement benefits
AOCI, Defined Benefit Plan, Beginning Balance	(497)	(499)	(422)	(429)	(499)	(429)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	3		9		5	16
AOCI, Defined Benefit Plan, Ending Balance	(494)	(497)	(413)	(422)	(494)	(413)
Net change in unrecognized periodic benefit costs for defined benefit pension and postretirement benefit plans, tax expense	(1)		(4)		(2)	(6)
Future Policy Benefits
AOCI, Liability for Future Policy Benefit, After Tax, Beginning Balance	15	13	(10)	(19)	13	(19)
Change in future policy benefits, net of tax	(3)		8		(1)	17
AOCI, Liability for Future Policy Benefit, After Tax, Ending Balance	12	15	(2)	(10)	12	(2)
Change in future policy benefits, tax expense	1		0		1	0
Foreign currency translation adjustments
AOCI, Foreign Currency Translation Adjustment, Net of Tax, Beginning Balance	(15)	(17)	(7)	(4)	(17)	(4)
Foreign currency translation adjustment, net of tax	0		(5)		2	(8)
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Ending Balance	(15)	$ (15)	(12)	$ (7)	(15)	(12)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax (Expense) Benefit	$ (5)		$ 1		$ (3)	$ 2