Available for Sale Securities - Summary of Amortized Costs and Fair Value of Securities Available-for-sale (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	$ 67,195	$ 57,145
Securities Available for Sale, Gross Unrealized Gains	1,215	1,588
Securities Available for Sale, Gross Unrealized Losses	(470)	(30)
Securities Available for Sale, Fair Value	67,940	58,703
Obligations of states and political subdivisions [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	11,772	11,570
Securities Available for Sale, Gross Unrealized Gains	187	244
Securities Available for Sale, Gross Unrealized Losses	(289)	(11)
Securities Available for Sale, Fair Value	11,670	11,803
Government-sponsored Mortgage-backed Securities [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	46,913	36,886
Securities Available for Sale, Gross Unrealized Gains	861	1,165
Securities Available for Sale, Gross Unrealized Losses	(181)	(12)
Securities Available for Sale, Fair Value	47,593	38,039
Asset-backed securities [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	7,052	7,231
Securities Available for Sale, Gross Unrealized Gains	64	57
Securities Available for Sale, Gross Unrealized Losses	0	(7)
Securities Available for Sale, Fair Value	7,116	7,281
Certificates of deposit [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	1,458	1,458
Securities Available for Sale, Gross Unrealized Gains	103	122
Securities Available for Sale, Fair Value	$ 1,561	$ 1,580

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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