Non-interest Income and Expense - Components of Non Interest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Other Income and Expenses [Abstract]
Base salaries, net of deferred loan origination costs	$ 17,623	$ 16,757
Incentive compensation	3,101	2,567
Benefits and other compensation costs	6,548	5,804
Total salaries and benefits expense	27,272	25,128
Occupancy	3,875	3,774
Data processing and software	3,367	3,349
Equipment	1,512	1,867
Intangible amortization	1,431	1,431
Advertising	665	1,331
ATM and POS network charges	1,373	1,323
Professional fees	703	839
Telecommunications	725	797
Regulatory assessments and insurance	95	511
Postage	290	310
Operational losses	221	225
Courier service	331	270
Gain on sale of foreclosed assets	(41)	(99)
Loss on disposal of fixed assets	0	24
Other miscellaneous expense	3,000	4,372
Total other non-interest expense	17,547	20,324
Total non-interest expense	$ 44,819	$ 45,452