Fair Value Measurements - Summary of Assets Measured at Fair Value on a Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans		$ 85
Foreclosed assets	$ 134
Total	134
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans		$ 85
Foreclosed assets	134
Total	$ 134