Loans - Summary of Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 07, 2018 USD ($) Contract	Jun. 30, 2017 USD ($) Contract	Jun. 30, 2018 USD ($) Contract	Jun. 30, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	1	5	1	5
Pre-Modification Recorded Investment	$ 200	$ 302	$ 200	$ 302
Post-Modification Recorded Investment	$ 200	$ 302	$ 200	$ 302
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract	1		1
Pre-Modification Recorded Investment	$ 200		$ 200
Post-Modification Recorded Investment	$ 200		$ 200
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract		4		4
Pre-Modification Recorded Investment		$ 288		$ 288
Post-Modification Recorded Investment		$ 288		$ 288
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of loans restructured \| Contract		1		1
Pre-Modification Recorded Investment		$ 14		$ 14
Post-Modification Recorded Investment		$ 14		$ 14

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Number of 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 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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