Securities Available-for-sale - Summary of Amortized Costs and Fair Value of Securities Available-for-sale (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	$ 67,560	$ 67,900
Securities Available for Sale, Gross Unrealized Gains	786	32
Securities Available for Sale, Gross Unrealized Losses	(211)	(2,201)
Securities Available for Sale, Fair Value	68,135	65,731
Obligations of States and Political Subdivisions [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	9,272	11,348
Securities Available for Sale, Gross Unrealized Gains	84	25
Securities Available for Sale, Gross Unrealized Losses	(7)	(204)
Securities Available for Sale, Fair Value	9,349	11,169
Government-sponsored Mortgage-backed Securities [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	53,572	52,363
Securities Available for Sale, Gross Unrealized Gains	635	4
Securities Available for Sale, Gross Unrealized Losses	(203)	(1,992)
Securities Available for Sale, Fair Value	54,004	50,375
Corporate Collateralized Mortgage Obligations [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	322	410
Securities Available for Sale, Gross Unrealized Gains	7	1
Securities Available for Sale, Gross Unrealized Losses		(1)
Securities Available for Sale, Fair Value	329	410
Asset-backed Securities [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	2,687	3,530
Securities Available for Sale, Gross Unrealized Gains	4	2
Securities Available for Sale, Gross Unrealized Losses	(1)	(1)
Securities Available for Sale, Fair Value	2,690	3,531
Certificates of Deposit [Member]
Marketable Securities [Line Items]
Securities Available for Sale, Amortized Cost	1,707	249
Securities Available for Sale, Gross Unrealized Gains	56
Securities Available for Sale, Gross Unrealized Losses		(3)
Securities Available for Sale, Fair Value	$ 1,763	$ 246

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=118939692&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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