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Securities - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Investments pledged, carrying value	$ 87,100	$ 88,800
Other securities	5,827	5,810
Federal Home Loan Bank of Cincinnati and Indianapolis Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Other securities	5,800	5,800
Ohio Equity Fund for Housing Limited Partnership [Member]
Schedule of Available-for-sale Securities [Line Items]
Other securities	$ 38	$ 21
Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Underwater security	10 years
Loss position existed	3 years

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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