Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disclosure Of Other Comprehensive Income Loss [Abstract]
(Gains) losses on securities available for sale	$ (169)	$ 2	$ (283)	$ 10
Tax effect	46		77	(2)
Net income	(123)	2	(206)	8
Net amortization of premium on securities	102	14	151	40
Tax effect	(28)	(4)	(41)	(11)
Net income	$ 74	$ 10	$ 110	$ 29

Disclosure of Other Comprehensive Income Loss

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