Securities Available for Sale - Schedule of Amortized Cost and Fair Value of Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 50,950	$ 51,417
Gross Unrealized Gains	61	635
Gross Unrealized Losses	(2,175)	(386)
Fair Value	48,836	51,666
U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	12,732	10,939
Gross Unrealized Losses	(687)	(168)
Fair Value	12,045	10,771
US Government-sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,996	1,995
Gross Unrealized Losses	(59)	(17)
Fair Value	1,937	1,978
Corporate [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,501	2,510
Gross Unrealized Gains		33
Gross Unrealized Losses	(80)	(7)
Fair Value	2,421	2,536
Municipal [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	350	351
Gross Unrealized Gains	1	2
Fair Value	351	353
Residential Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,447	23,349
Gross Unrealized Gains	60	324
Gross Unrealized Losses	(1,031)	(194)
Fair Value	20,476	23,479
Commercial Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,701	8,733
Gross Unrealized Gains		223
Gross Unrealized Losses	(211)
Fair Value	8,490	8,956
Commercial Mortgage Backed Securities, U.S. Government-guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		103
Fair Value		103
Collateralized Mortgage Obligations, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	749	796
Gross Unrealized Gains		14
Gross Unrealized Losses	(22)
Fair Value	727	810
Collateralized Mortgage Obligations, US Government Guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,474	2,641
Gross Unrealized Gains		39
Gross Unrealized Losses	(85)
Fair Value	$ 2,389	$ 2,680

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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