Loans - Summary of Nonperforming Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Modifications [Line Items]
Nonaccrual loans, other than troubled debt restructurings	$ 906	$ 1,058
Total nonperforming loans (NPLs)	1,555	1,887
Accruing Loans [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	459	729
Non Accruing Loan [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	$ 649	$ 829

Amount of financing receivable on nonaccrual status other than troubled debt restructurings

No definition available.

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Balance Type:	debit
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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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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

+ Details

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- Details

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- Details

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