Retirement Benefits (Schedule Of Defined Benefit Plan Net Periodic Benefit Cost Amounts Recorded in Consolidated Statement of Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Compensation and benefits expense (Operating income)	$ (540)	$ (467)	$ (2,495)	$ (2,085)
Other net benefit (credits) cost	(60)	(69)	(187)	(203)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Compensation and benefits expense (Operating income)	10	10	27	28
Other net benefit (credits) cost	(60)	(69)	(187)	(203)
Total (credit) cost	(50)	(59)	(160)	(175)
Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Compensation and benefits expense (Operating income)	0	0	0	0
Other net benefit (credits) cost	0	0	0	0
Total (credit) cost	$ 0	$ 0	$ 0	$ 0