Securities - Aggregate Amortized Cost and Fair Values of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 83,804	$ 77,773
Gross Unrealized Gains	118	224
Gross Unrealized (Losses)	(1,690)	(844)
Securities available-for-sale, at fair value	82,232	77,153
US Government Agencies Agencies and Mortgage Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	51,126	49,964
Gross Unrealized Gains	35	6
Gross Unrealized (Losses)	(1,279)	(687)
Securities available-for-sale, at fair value	49,882	49,283
State and Municipal Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,484	21,113
Gross Unrealized Gains	60	195
Gross Unrealized (Losses)	(327)	(155)
Securities available-for-sale, at fair value	20,217	21,153
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	12,194	6,696
Gross Unrealized Gains	23	23
Gross Unrealized (Losses)	(84)	(2)
Securities available-for-sale, at fair value	$ 12,133	$ 6,717

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).

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)
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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).

+ References

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-Publisher FASB
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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
-Topic 320
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-Section 50
-Paragraph 2
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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