Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Net income	$ 763	$ 549	$ 747	$ 604	$ 1,312	$ 1,351
Preferred stock dividends	(37)		(35)		(60)	(55)
Dividends and undistributed earnings allocated to participating securities	0		0		(1)	(1)
Net income available to common shareholders, basic	726		712		1,251	1,295
Net income available to common shareholders, diluted	$ 726		$ 712		$ 1,251	$ 1,295
Basic average common shares (in shares)	329,383		367,375		335,212	366,961
Effect of dilutive securities: equity-based awards (in shares)	4,157		4,748		4,261	5,119
Diluted average common shares (in shares)	333,540		372,123		339,473	372,080
Anti-dilutive securities (in shares)	2,282		1,990		1,380	741
Earnings per common share, basic:
Basic (in USD per share)	$ 2.20		$ 1.94		$ 3.73	$ 3.53
Earnings per common share, diluted:
Diluted (in USD per share)	$ 2.17		$ 1.91		$ 3.68	$ 3.48