Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Net income	$ 604	$ 519
Preferred stock dividends	(20)	(30)
Dividends and undistributed earnings allocated to participating securities	(1)	0
Net income available to common shareholders	583	489
Net income available to common shareholders	$ 583	$ 489
Basic average common shares (in shares)	366,542	350,743
Effect of dilutive securities: common stock options and common stock awards (in shares)	5,495	4,947
Diluted average common shares (in shares)	372,037	355,690
Anti-dilutive securities (in shares)	8	255
Earnings per common share:
Basic (in USD per share)	$ 1.59	$ 1.39
Diluted (in USD per share)	$ 1.57	$ 1.37