Stockholders' Equity (Summary Of Dividends Paid On Common Stock) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stockholders Equity [Line Items]
Dividends amount	$ 299	$ 596
Dividends rate per share	$ 0.44	$ 0.89
Fixed Dividend [Member]
Stockholders Equity [Line Items]
Dividends amount	$ 143	$ 133
Dividends rate per share	$ 0.22	$ 0.2
Variable Dividend [Member]
Stockholders Equity [Line Items]
Dividends amount	$ 156	$ 463