Earnings Per Common Share - Computations of Basic Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income available to common shareholders:
Net income	$ 217,522	$ 458,069	$ 579,696	$ 905,318
Less: Preferred stock dividends	(24,941)	(17,050)	(46,706)	(34,100)
Net income available to common equity	192,581	441,019	532,990	871,218
Less: Income attributable to unvested stock-based compensation awards	(345)	(2,263)	(1,076)	(4,370)
Net income available to common shareholders	$ 192,236	$ 438,756	$ 531,914	$ 866,848
Weighted-average shares outstanding:
Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards	177,682	129,589	153,612	129,502
Less: Unvested stock-based compensation awards	(315)	(918)	(322)	(898)
Weighted-average shares outstanding	177,367	128,671	153,290	128,604
Basic earnings per common share	$ 1.08	$ 3.41	$ 3.47	$ 6.74