Stockholders' Equity (Summary Of Dividends Paid On Common Stock) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Stockholders Equity [Line Items]
Dividends amount	$ 223	$ 299	$ 462	$ 596
Dividends rate per share	$ 0.35	$ 0.44	$ 0.72	$ 0.89
Total year to date	$ 522		$ 1,058		$ 522	$ 1,058
Fixed Dividend [Member]
Stockholders Equity [Line Items]
Dividends amount	138	$ 143	128	$ 133
Dividends rate per share					$ 0.22	$ 0.2
Total year to date	281		261		$ 281	$ 261
Variable Dividend [Member]
Stockholders Equity [Line Items]
Dividends amount	85	$ 156	334	$ 463
Total year to date	$ 241		$ 797		$ 241	$ 797