Earnings Per Common Share - Computations of Basic Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income available to common shareholders:
Net Income (Loss)	$ 2,741	$ 1,992	$ 1,859
Less: Preferred stock dividends	(100)	(97)	(73)
Net income available to common equity	2,641	1,895	1,786
Less: Income attributable to unvested stock-based compensation awards	(5)	(4)	(9)
Net income available to common shareholders	$ 2,636	$ 1,891	$ 1,777
Weighted-average shares outstanding:
Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards	166,662	163,489	129,539
Less: Unvested stock-based compensation awards	(301)	(315)	(890)
Weighted-average shares outstanding	166,361	163,174	128,649
Basic earnings per common share	$ 15.85	$ 11.59	$ 13.81