Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings Per Share [Abstract]
Net income	$ 422	$ 763	$ 549	$ 690	$ 747	$ 604	$ 1,734	$ 2,041
Preferred stock dividends	(24)			(21)			(84)	(76)
Dividends and undistributed earnings allocated to participating securities	0			0			(1)	(1)
Net income available to common shareholders, basic	398			669			1,649	1,964
Net income available to common shareholders, diluted	$ 398			$ 669			$ 1,649	$ 1,964
Basic average common shares (in shares)	313,147			367,789			327,776	367,240
Effect of dilutive securities: equity-based awards (in shares)	4,182			4,629			4,235	4,954
Diluted average common shares (in shares)	317,329			372,418			332,011	372,194
Anti-dilutive securities (in shares)	1,683			1,592			1,368	904
Earnings per common share, basic:
Basic (in USD per share)	$ 1.27			$ 1.82			$ 5.03	$ 5.35
Earnings per common share, diluted:
Diluted (in USD per share)	$ 1.25			$ 1.80			$ 4.97	$ 5.28