Loans - Summary of Troubled Debt Restructurings (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Contract	Dec. 31, 2018 USD ($) Contract	Dec. 31, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract	1	3	8
Pre-Modification Recorded Investment	$ 17	$ 227	$ 490
Post-Modification Recorded Investment	$ 17	$ 227	$ 490
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract	1
Pre-Modification Recorded Investment	$ 17
Post-Modification Recorded Investment	$ 17
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract		1	2
Pre-Modification Recorded Investment		$ 200	$ 150
Post-Modification Recorded Investment		$ 200	$ 150
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract		2	2
Pre-Modification Recorded Investment		$ 27	$ 52
Post-Modification Recorded Investment		$ 27	$ 52
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract			4
Pre-Modification Recorded Investment			$ 288
Post-Modification Recorded Investment			$ 288

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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=118936363&loc=SL6953676-111524

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

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

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