Securities Available-for-Sale - Schedule of amortized cost and fair value of securities available-for-sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized Cost	$ 42,696	$ 44,070
Gross Unrealized Gains	1,564	815
Gross Unrealized Losses	(37)	(100)
Fair Value	44,223	44,785
U.S. Government-sponsored enterprises obligations [Member]
Amortized Cost	1,000	9,000
Gross Unrealized Gains	11	11
Gross Unrealized Losses		(14)
Fair Value	1,011	8,997
U.S. Government agency small business administration pools guaranteed by SBA [Member]
Amortized Cost	2,620	2,760
Gross Unrealized Gains	61
Gross Unrealized Losses		(20)
Fair Value	2,681	2,740
Collateralized mortgage obligations issued by the FHLMC [Member]
Amortized Cost	772	986
Gross Unrealized Gains	15
Gross Unrealized Losses		(6)
Fair Value	787	980
Residential mortgage backed securities [Member]
Amortized Cost	2,684	3,186
Gross Unrealized Gains	75	4
Gross Unrealized Losses		(2)
Fair Value	2,759	3,188
Municipal bonds [Member]
Amortized Cost	35,620	28,138
Gross Unrealized Gains	1,402	800
Gross Unrealized Losses	(37)	(58)
Fair Value	$ 36,985	$ 28,880

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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