Fair Values of Assets and Liabilities - Fair Value, by Balance Sheet Grouping (Detail) - USD ($) $ in Thousands	Dec. 31, 2021		Dec. 31, 2020
Securities available-for-sale:
Securities available-for-sale, at fair value	$ 91,365		$ 55,470
Securities available-for-sale, at fair value	91,365		55,470
U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	5,971		973
Securities available-for-sale, at fair value	5,971		973
U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	5,045		2,470
Securities available-for-sale, at fair value	5,045		2,470
Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	3,332	[1]	949
Securities available-for-sale, at fair value	3,332	[1]	949
Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	23,332	[1]	5,136
Securities available-for-sale, at fair value	23,332	[1]	5,136
Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	50,613		45,942
Securities available-for-sale, at fair value	50,613		45,942
Fair Value, Measurements, Recurring [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	3,072
Securities available-for-sale, at fair value	3,072
Fair Value, Measurements, Recurring [Member] | U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	5,971		973
Securities available-for-sale, at fair value	5,971		973
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	5,045		2,470
Securities available-for-sale, at fair value	5,045		2,470
Fair Value, Measurements, Recurring [Member] | Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	3,332		949
Securities available-for-sale, at fair value	3,332		949
Fair Value, Measurements, Recurring [Member] | Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	23,332		5,136
Securities available-for-sale, at fair value	23,332		5,136
Fair Value, Measurements, Recurring [Member] | Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	50,613		45,942
Securities available-for-sale, at fair value	50,613		45,942
Fair Value, Measurements, Recurring [Member] | Derivative [Member]
Assets, Fair Value Disclosure
Liabilities, Fair Value Disclosure	200		137
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	322		273
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	3,072
Securities available-for-sale, at fair value	3,072
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	5,971		973
Securities available-for-sale, at fair value	5,971		973
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	5,045		2,470
Securities available-for-sale, at fair value	5,045		2,470
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	3,332		949
Securities available-for-sale, at fair value	3,332		949
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	23,332		5,136
Securities available-for-sale, at fair value	23,332		5,136
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	50,613		45,942
Securities available-for-sale, at fair value	50,613		45,942
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member]
Assets, Fair Value Disclosure
Liabilities, Fair Value Disclosure	200		137
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage servicing rights [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	$ 322		$ 273

[1] Actual maturities for these debt securities are dependent upon the interest rate environment and prepayments on the underlying loans.