Loans - Summary of Troubled Debt Restructurings (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract	5	6
Pre-Modification Recorded Investment	$ 3,708	$ 455
Post-Modification Recorded Investment	$ 3,708	$ 455
Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract	4	1
Pre-Modification Recorded Investment	$ 3,607	$ 148
Post-Modification Recorded Investment	$ 3,607	$ 148
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number Of Loans Restructured \| Contract	1	5
Pre-Modification Recorded Investment	$ 101	$ 307
Post-Modification Recorded Investment	$ 101	$ 307

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&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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