Loans, Leases and Other Real Estate - Summary of Restructured Loans (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 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 Contracts \| Contract	2	4	4	6
Pre- Modification Outstanding Recorded Investment	$ 1,120	$ 283	$ 2,777	$ 3,162
Post- Modification Outstanding Recorded Investment	$ 1,120	$ 283	$ 2,777	$ 3,162
Commercial, secured by real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1	2	3	4
Pre- Modification Outstanding Recorded Investment	$ 170	$ 159	$ 1,827	$ 3,038
Post- Modification Outstanding Recorded Investment	$ 170	$ 159	$ 1,827	$ 3,038
Commercial, industrial and other
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1	2	1	2
Pre- Modification Outstanding Recorded Investment	$ 950	$ 124	$ 950	$ 124
Post- Modification Outstanding Recorded Investment	$ 950	$ 124	$ 950	$ 124

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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=84173941&loc=SL6953676-111524

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

+ References

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

+ References

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