Earnings Per Common Share - Computations of Diluted 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
Earnings Per Share [Abstract]
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
Adjusted 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)
Plus: Incremental shares from assumed conversion of stock-based compensation awards and warrants to purchase common stock	641	856	163
Adjusted weighted-average shares outstanding	167,002	164,030	128,812
Diluted earnings per common share	$ 15.79	$ 11.53	$ 13.8