Loans - Summary of Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020 USD ($) Contract	Jun. 30, 2019 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	12	13
Pre-Modification Recorded Investment	$ 404	$ 473
Post-Modification Recorded Investment	$ 404	$ 473
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	4	5
Pre-Modification Recorded Investment	$ 112	$ 181
Post-Modification Recorded Investment	$ 112	$ 181
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	1	1
Pre-Modification Recorded Investment	$ 80	$ 80
Post-Modification Recorded Investment	$ 80	$ 80
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	1	1
Pre-Modification Recorded Investment	$ 66	$ 66
Post-Modification Recorded Investment	$ 66	$ 66
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	6	6
Pre-Modification Recorded Investment	$ 146	$ 146
Post-Modification Recorded Investment	$ 146	$ 146

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.

No definition available.

+ Details

Name:	us-gaap_FinancingReceivableModificationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: