Non-interest Income and Expense - Components of Non-Interest Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule Of Other Noninterest Income And Expense [Line Items]
Total service charges and fees	$ 10,930	$ 8,168	$ 21,406	$ 17,294
Increase in cash value of life insurance	745	710	1,418	1,430
Asset management and commission income	947	661	1,781	1,577
Gain on sale of loans	2,847	1,736	6,094	2,627
Lease brokerage income	249	127	359	320
Sale of customer checks	116	88	235	212
Gain on sale of investment securities	0	0	0	0
Gain (loss) on marketable equity securities	8	25	(45)	72
Other	115	142	819	(55)
Total other non-interest income	5,027	3,489	10,661	6,183
Total non-interest income	15,957	11,657	32,067	23,477
ATM and interchange fees
Schedule Of Other Noninterest Income And Expense [Line Items]
Total service charges and fees	6,558	5,165	12,419	10,276
Service charges on deposit accounts
Schedule Of Other Noninterest Income And Expense [Line Items]
Total service charges and fees	3,462	3,046	6,731	7,092
Other service fees
Schedule Of Other Noninterest Income And Expense [Line Items]
Total service charges and fees	914	734	1,785	1,492
Mortgage banking service fees
Schedule Of Other Noninterest Income And Expense [Line Items]
Total service charges and fees	467	459	930	928
Change in value of mortgage servicing rights
Schedule Of Other Noninterest Income And Expense [Line Items]
Total service charges and fees	$ (471)	$ (1,236)	$ (459)	$ (2,494)