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, 2024	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Net income available to common equity	$ 2,454	$ 2,641	$ 1,895
Less: Income attributable to unvested stock-based compensation awards	(5)	(5)	(4)
Net income available to common shareholders	$ 2,449	$ 2,636	$ 1,891
Adjusted weighted-average shares outstanding:
Common shares outstanding (in shares)	166,806	166,662	163,489
Unvested stock awards (in shares)	(327)	(301)	(315)
Incremental common shares (in shares)	840	641	856
Average common shares outstanding, diluted (in shares)	167,319	167,002	164,030
Diluted earnings per common share (in USD per share)	$ 14.64	$ 15.79	$ 11.53