Borrowings - Schedule of Federal Home Loan Bank Advances by Branch of FHLB Bank (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Principal Amounts	$ 51,312	$ 66,219
Federal Home Loan Bank Advances One [Member]
Principal Amounts	$ 10,000	$ 44,907
Maturity Dates	2020	2020
Federal Home Loan Bank Advances One [Member] \| Minimum [Member]
Interest Rates	0.60%	1.77%
Federal Home Loan Bank Advances One [Member] \| Maximum [Member]
Interest Rates	2.15%	2.19%
Federal Home Loan Bank Advances Two [Member]
Principal Amounts	$ 2,262	$ 2,262
Maturity Dates	2022	2022
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Three [Member]
Principal Amounts	$ 18,800	$ 18,800
Maturity Dates	2024	2024
Federal Home Loan Bank Advances Three [Member] \| Minimum [Member]
Interest Rates	0.00%	0.00%
Federal Home Loan Bank Advances Three [Member] \| Maximum [Member]
Interest Rates	1.69%	1.69%
Federal Home Loan Bank Advances Four [Member]
Principal Amounts	$ 20,000	$ 250
Maturity Dates	2025	2028
Interest Rates		0.00%
Federal Home Loan Bank Advances Four [Member] \| Minimum [Member]
Interest Rates	1.35%
Federal Home Loan Bank Advances Four [Member] \| Maximum [Member]
Interest Rates	1.52%
Federal Home Loan Bank Advances Five [Member]
Principal Amounts	$ 250
Maturity Dates	2028
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=75038535&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
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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