Earnings Per Common Share - Basic and Diluted Earnings Per Common Share (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net income	$ 116,015	$ 54,753
Less: Preferred stock dividends	2,151	2,016
Redemption of preferred stock	0	5,514
Net income available to common shareholders	113,864	47,223
Less: Earnings allocated to participating securities	1,162	445
Distributed earnings allocated to common stock	45,660	44,512
Undistributed earnings allocated to common stock	67,042	2,266
Net earnings allocated to common stock	$ 112,702	$ 46,778
Weighted-average shares outstanding for basic earnings per common share	63,306,493	62,642,682
Dilutive effect of stock compensation	509,290	407,154
Weighted-average shares outstanding for diluted earnings per common share	63,815,783	63,049,836