Earnings Per Common Share - Computations of Basic Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income available to common shareholders:
Net Income (Loss)	$ 531	$ 702
Less: Preferred stock dividends	(25)	(25)
Net income available to common equity	506	677
Less: Income attributable to unvested stock-based compensation awards	(1)	(1)
Net income available to common shareholders	$ 505	$ 676
Weighted-average shares outstanding:
Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards	166,738	168,010
Less: Unvested stock-based compensation awards	(278)	(278)
Weighted-average shares outstanding	166,460	167,732
Basic earnings per common share	$ 3.04	$ 4.03