Revenue from Contracts with Customers - Schedule of Revenue from Contracts (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Net interest income	$ 25,201	$ 23,438
Noninterest income:
Service charges on deposit accounts	2,296	2,209
Lockbox fees	930	1,089
Gains on sales of mortgage loans		15
Other income	1,084	1,114
Total noninterest income	4,310	4,427
ASU 2014-09 [Member]
Disaggregation of Revenue [Line Items]
Net interest income	25,201	23,438
Noninterest income:
Service charges on deposit accounts	2,296	2,209
Lockbox fees	930	1,089
Gains on sales of mortgage loans		15
Other income	1,084	1,114
Total noninterest income	4,310	4,427
Total revenues	29,511	27,865
ASU 2014-09 [Member] | Revenue Guidance Contracts in Scope of Topic 606 [Member]
Noninterest income:
Service charges on deposit accounts	2,296	2,209
Lockbox fees	930	1,089
Other income	599	800
Total noninterest income	3,825	4,098
Total revenues	$ 3,825	$ 4,098