Borrowings - Schedule of Federal Home Loan Bank Advances by Branch of FHLB Bank (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Principal Amounts	$ 29,462	$ 34,127
Federal Home Loan Bank Advances One
Principal Amounts	$ 12,262	$ 10,095
Maturity Dates	2022	2021
Federal Home Loan Bank Advances One \| Minimum [Member]
Interest Rates	0.00%	0.39%
Federal Home Loan Bank Advances One \| Maximum
Interest Rates	0.31%	0.42%
Federal Home Loan Bank Advances Two
Principal Amounts	$ 15,000	$ 2,262
Maturity Dates	2023	2022
Interest Rates		0.00%
Federal Home Loan Bank Advances Two \| Minimum [Member]
Interest Rates	0.44%
Federal Home Loan Bank Advances Two \| Maximum
Interest Rates	0.45%
Federal Home Loan Bank Advances Three
Principal Amounts	$ 800	$ 10,800
Maturity Dates	2024
Interest Rates	0.00%
Federal Home Loan Bank Advances Three \| Minimum [Member]
Interest Rates		0.00%
Federal Home Loan Bank Advances Three \| Maximum
Interest Rates		1.39%
Federal Home Loan Bank Advances Four
Principal Amounts	$ 520	$ 10,520
Maturity Dates	2025	2025
Interest Rates	0.00%
Federal Home Loan Bank Advances Four \| Minimum [Member]
Interest Rates		0.00%
Federal Home Loan Bank Advances Four \| Maximum
Interest Rates		1.35%
Federal Home Loan Bank Advances Five
Principal Amounts	$ 250	$ 250
Maturity Dates	2028	2028
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Six
Principal Amounts	$ 200	$ 200
Maturity Dates	2030	2030
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Seven
Principal Amounts	$ 430
Maturity Dates	2031
Interest Rates	0.00%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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- Definition

The year of maturity, when only one maturity date applies, for the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

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