Condensed Parent Company Financial Statements- Summary of Income Statement of Parent Company (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
OPERATING INCOME
Interest on interest-bearing deposits	$ 119,260	$ 58,848	$ 4,366
OPERATING EXPENSE
Other	50,009	53,258	54,051
Allocated income tax benefit	(57,483)	(44,332)	(40,768)
Amortization of stock-based compensation arrangements of subsidiaries	(2,999)	(1,941)	(2,133)
Net income	212,465	193,100	167,630
Parent Company [Member]
OPERATING INCOME
Dividends from subsidiaries	137,275	93,139	54,480
Interest on interest-bearing deposits	1,178	94	41
Other	726	1,338	1,071
Total operating income	139,179	94,571	55,592
OPERATING EXPENSE
Interest	4,122	4,122	3,130
Other	3,206	7,190	3,340
Total operating expense	7,328	11,312	6,470
Income before taxes	131,851	83,259	49,122
Allocated income tax benefit	2,249	5,857	4,191
Income before equity in undistributed earnings of subsidiaries	134,100	89,116	53,313
Equity in undistributed earnings of subsidiaries	81,275	105,817	116,365
Amortization of stock-based compensation arrangements of subsidiaries	(2,910)	(1,833)	(2,048)
Net income	$ 212,465	$ 193,100	$ 167,630