Fair Values of Assets and Liabilities - Fair Value, by Balance Sheet Grouping (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Securities available-for-sale:
Securities available-for-sale, at fair value	$ 44,223	$ 44,785
U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,011	8,997
U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	2,681	2,740
Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	36,985	28,880
Fair Value, Measurements, Recurring [Member] | U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,011	8,997
Fair Value, Measurements, Recurring [Member] | U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	2,681	2,740
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Obligations Issued by the FHLMC [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	787	980
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	2,759	3,188
Fair Value, Measurements, Recurring [Member] | Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	36,985	28,880
Fair Value, Measurements, Recurring [Member] | Derivative [Member]
Other liabilities:
Liabilities, Fair Value Disclosure	164
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,011	8,997
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	2,681	2,740
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Collateralized Mortgage Obligations Issued by the FHLMC [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	787	980
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	2,759	3,188
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	36,985	28,880
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member]
Other liabilities:
Liabilities, Fair Value Disclosure	164
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member]
Other assets:
Assets, Fair Value Disclosure	329	397
Fair Value, Measurements, Recurring [Member] | Mortgage-backed securities [Member] | Fair Value, Inputs, Level 3 [Member]
Other assets:
Assets, Fair Value Disclosure	$ 329	$ 397