Loans and Leases and Other Real Estate - Summary of Restructured Loans (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Contract	Dec. 31, 2016 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	16	5
Pre- Modification Outstanding Recorded Investment	$ 4,807	$ 843
Post- Modification Outstanding Recorded Investment	$ 4,807	$ 843
Commercial, secured by real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	8	1
Pre- Modification Outstanding Recorded Investment	$ 4,618	$ 303
Post- Modification Outstanding Recorded Investment	$ 4,618	$ 303
Commercial, industrial and other
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	2	0
Pre- Modification Outstanding Recorded Investment	$ 124	$ 0
Post- Modification Outstanding Recorded Investment	$ 124	$ 0
Leases
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	6	0
Pre- Modification Outstanding Recorded Investment	$ 65	$ 0
Post- Modification Outstanding Recorded Investment	$ 65	$ 0
Real estate - residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	1
Pre- Modification Outstanding Recorded Investment	$ 0	$ 255
Post- Modification Outstanding Recorded Investment	$ 0	$ 255
Home equity and consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	3
Pre- Modification Outstanding Recorded Investment	$ 0	$ 285
Post- Modification Outstanding Recorded Investment	$ 0	$ 285

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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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