Securities Available-for-Sale - Schedule of amortized cost and fair values of available-for-sale securities by contractual maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Due after five years through ten years, Amortized Cost	$ 1,000
Due after ten years, Amortized Cost	35,620
Total U.S. Government-sponsored enterprises obligations and municipal bonds, Amortized Cost	36,620
Mortgage-backed securities, Amortized Cost	42,696	$ 44,070
Due after five years through ten years, Fair Value	1,011
Due after ten years, Fair Value	36,985
Total U.S. Government-sponsored enterprises obligations and municipal bonds, Fair Value	37,996
Mortgage-backed securities, Fair Value	44,223	44,785
U.S. Government agency small business pools guaranteed by SBA [Member]
Mortgage-backed securities, Amortized Cost	2,620	2,760
Mortgage-backed securities, Fair Value	2,681	2,740
Collateralized mortgage obligations issued by the FHLMC [Member]
Mortgage-backed securities, Amortized Cost	772	986
Mortgage-backed securities, Fair Value	787	980
Residential mortgage-backed securities
Mortgage-backed securities, Amortized Cost	2,684	3,186
Mortgage-backed securities, Fair Value	$ 2,759	$ 3,188

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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