Revenue Recognition - Summary of Noninterest Income Segregated By Revenue Streams In-scope and Out-of-scope of Topic 606 (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Noninterest income
Service charges	$ 1,456	$ 1,134
ATM/Interchange fees	906	554
Wealth management fees	847	852
Tax refund processing fees	2,200	2,200
Other	131	220
Noninterest Income (in-scope of Topic 606)	5,540	4,960
Noninterest Income (out-of-scope of Topic 606)	744	656
Total noninterest income	$ 6,284	$ 5,616