Equity Compensation Plans (Schedule Of Equity Based Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment Arrangement [Abstract]
Stock options	$ 43	$ 43	$ 45
Restricted stock/RSUs	58	62	65
Total equity-based compensation expense, net of tax	$ 101	$ 105	$ 110