Fair Value Measurements And Disclosure (Gain and Losses on Equity Securities) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Total gains (losses) recognized on equity securities	$ 209	$ 257	$ (309)
Gains (Losses) recognized on equity securities sold	(52)	89	(80)
Unrealized gains (losses) recognized on equity securities held at end of period	$ 261	$ 168	$ (229)