Securities Available for Sale - Schedule of Amortized Cost and Fair Value of Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 53,353	$ 53,654
Gross Unrealized Gains	1,112	1,712
Gross Unrealized Losses	(317)
Fair Value	54,148	55,366
Debt Securities [Member] \| U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,913
Gross Unrealized Losses	(90)
Fair Value	3,823
Debt Securities [Member] \| US Government-sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,993	1,993
Gross Unrealized Gains		3
Gross Unrealized Losses	(2)
Fair Value	1,991	1,996
Debt Securities [Member] \| Corporate [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,286	4,300
Gross Unrealized Gains	15	56
Gross Unrealized Losses	(5)
Fair Value	4,296	4,356
Debt Securities [Member] \| Municipal [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	595	595
Gross Unrealized Gains	3	5
Fair Value	598	600
Debt Securities [Member] \| Residential Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	29,023	32,538
Gross Unrealized Gains	623	919
Gross Unrealized Losses	(220)
Fair Value	29,426	33,457
Debt Securities [Member] \| Commercial Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,825	8,857
Gross Unrealized Gains	361	525
Fair Value	9,186	9,382
Debt Securities [Member] \| Commercial Mortgage Backed Securities, U.S. Government-guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	559	977
Gross Unrealized Gains	9	24
Fair Value	568	1,001
Debt Securities [Member] \| Collateralized Mortgage Obligations, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	944	996
Gross Unrealized Gains	41	52
Fair Value	985	1,048
Debt Securities [Member] \| Collateralized Mortgage Obligations, US Government Guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,215	3,398
Gross Unrealized Gains	60	128
Fair Value	$ 3,275	$ 3,526

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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