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		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Compensation and benefits expense (Operating income)	$ (1,228)	$ (885)	$ (2,586)	$ (1,955)
Other net benefit (credits) cost	(71)	(63)	(142)	(127)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Compensation and benefits expense (Operating income)	10	9	20	17
Other net benefit (credits) cost	(72)	(63)	(143)	(127)
Total (credit) cost	(62)	(54)	(123)	(110)
Post-retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Compensation and benefits expense (Operating income)	0	0	0	0
Other net benefit (credits) cost	1	0	1	0
Total (credit) cost	$ 1	$ 0	$ 1	$ 0