Available for Sale Securities - Summary of Amortized Costs and Fair Value of Securities Available-for-sale (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	$ 57,145	$ 71,229
Securities Available for Sale, Gross Unrealized Gains	1,588	542
Securities Available for Sale, Gross Unrealized Losses	(30)	(396)
Securities Available for Sale, Fair Value	58,703	71,375
Obligations of states and political subdivisions [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	11,570	9,779
Securities Available for Sale, Gross Unrealized Gains	244	67
Securities Available for Sale, Gross Unrealized Losses	(11)	(20)
Securities Available for Sale, Fair Value	11,803	9,826
Government-sponsored Mortgage-backed Securities [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	36,886	56,975
Securities Available for Sale, Gross Unrealized Gains	1,165	416
Securities Available for Sale, Gross Unrealized Losses	(12)	(357)
Securities Available for Sale, Fair Value	38,039	57,034
Corporate collateralized mortgage obligations [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost		284
Securities Available for Sale, Gross Unrealized Gains		5
Securities Available for Sale, Fair Value		289
Asset-backed securities [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	7,231	2,484
Securities Available for Sale, Gross Unrealized Gains	57
Securities Available for Sale, Gross Unrealized Losses	(7)	(19)
Securities Available for Sale, Fair Value	7,281	2,465
Certificates of deposit [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	1,458	1,707
Securities Available for Sale, Gross Unrealized Gains	122	54
Securities Available for Sale, Fair Value	$ 1,580	$ 1,761

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

+ Details

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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.

+ Details

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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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