Loans, Leases and Other Real Estate - Summary of Restructured Loans (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($) Contract	Sep. 30, 2017 USD ($) Contract	Sep. 30, 2018 USD ($) Contract	Sep. 30, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1	1	5	7
Pre- Modification Outstanding Recorded Investment	$ 1,175	$ 473	$ 3,952	$ 3,635
Post- Modification Outstanding Recorded Investment	$ 1,175	$ 473	$ 3,952	$ 3,635
Commercial, secured by real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	1	1	4	5
Pre- Modification Outstanding Recorded Investment	$ 1,175	$ 473	$ 3,002	$ 3,511
Post- Modification Outstanding Recorded Investment	$ 1,175	$ 473	$ 3,002	$ 3,511
Commercial, industrial and other
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract			1	2
Pre- Modification Outstanding Recorded Investment			$ 950	$ 124
Post- Modification Outstanding Recorded Investment			$ 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.

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