Income Taxes (Schedule Of Income Tax Expense/(Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
U.S. federal	$ 1,873	$ 1,276	$ 1,193
Non-U.S.	169	149	133
U.S. state	97	23	15
Total Current Income Tax Expense (Benefit)	2,139	1,448	1,341
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
U.S. federal	(996)	204	(544)
Non-U.S.	(4)	3	(4)
U.S. state	5	(6)	(44)
Total deferred	(995)	201	(592)
Income Tax Expense (Benefit), Continuing Operations [Abstract]
Total income tax expense	$ 1,144	$ 1,649	$ 749