Fair Value Measurements - Summary of Assets Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, net	$ 4,229	$ 4,700
Other real estate owned, net	3,168	3,597
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, net	4,229	4,700
Other real estate owned, net	3,168	3,597
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans, net	4,229	4,700
Other real estate owned, net	$ 3,168	$ 3,597