Securities - Aggregate Amortized Cost, Unrealized Gains and Losses, and Fair Values of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 98,894	$ 83,804
Gross Unrealized Gains	741	118
Gross Unrealized (Losses)	(181)	(1,690)
Fair Value	99,454	82,232
US Government Agencies and Mortgage Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	67,491	51,126
Gross Unrealized Gains	284	35
Gross Unrealized (Losses)	(178)	(1,279)
Fair Value	67,597	49,882
State and Municipal Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,238	20,484
Gross Unrealized Gains	341	60
Gross Unrealized (Losses)	(3)	(327)
Fair Value	16,576	20,217
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	15,165	12,194
Gross Unrealized Gains	116	23
Gross Unrealized (Losses)		(84)
Fair Value	$ 15,281	$ 12,133

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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