Earnings Per Common Share - Summary of Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator for both basic and diluted earnings per common share:
Net income available to common shareholders	$ 50,502	$ 41,877	$ 132,309	$ 180,518
Denominator:
Total average basic common shares outstanding	59,549,244	64,931,764	60,336,637	66,354,750
Effect of dilutive stock options and other stock compensation	148,432	134,084	152,611	155,607
Total diluted average common shares outstanding	59,697,676	65,065,848	60,489,248	66,510,357
Earnings per common share - basic	$ 0.85	$ 0.64	$ 2.19	$ 2.72
Earnings per common share - diluted	$ 0.85	$ 0.64	$ 2.19	$ 2.71