Earnings Per Common Share - Computations of Diluted 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
Earnings Per Share [Abstract]
Net income available to common equity	$ 192,581	$ 441,019	$ 532,990	$ 871,218
Less: Income attributable to unvested stock-based compensation awards	(345)	(2,260)	(1,074)	(4,366)
Net income available to common shareholders	$ 192,236	$ 438,759	$ 531,916	$ 866,852
Adjusted weighted-average shares outstanding:
Common and unvested stock-based compensation awards	177,682	129,589	153,612	129,502
Less: Unvested stock-based compensation awards	(315)	(918)	(322)	(898)
Plus: Incremental shares from assumed conversion of stock-based compensation awards and warrants to purchase common stock	910	171	691	152
Adjusted weighted-average shares outstanding	178,277	128,842	153,981	128,756
Diluted earnings per common share	$ 1.08	$ 3.41	$ 3.45	$ 6.73