Loans - Nonaccrual Loans and Loans Past Due over 90 Days Still Accruing (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	$ 24,318	$ 19,232
Past Due Over 90 Days Still on Accrual	345	477
Commercial, Industrial, and Agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	8,193	1,869
Past Due Over 90 Days Still on Accrual	0	78
Commercial mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	10,207	11,065
Past Due Over 90 Days Still on Accrual	0	0
Residential Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	5,272	5,470
Past Due Over 90 Days Still on Accrual	301	338
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	646	828
Past Due Over 90 Days Still on Accrual	10	17
Credit Cards
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
Past Due Over 90 Days Still on Accrual	$ 34	$ 44

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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