Loans - Nonaccrual Loans and Loans Past Due over 90 Days Still Accruing Interest by Class of Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	$ 12,161	$ 9,190
Past Due Over 90 Days Still on Accrual	193	213
Commercial, Industrial, and Agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	3,346	796
Past Due Over 90 Days Still on Accrual	0	0
Commercial Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	4,176	4,323
Past Due Over 90 Days Still on Accrual	0	0
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	3,715	3,026
Past Due Over 90 Days Still on Accrual	104	213
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	924	1,045
Past Due Over 90 Days Still on Accrual	89	0
Credit Cards [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	0
Past Due Over 90 Days Still on Accrual	$ 0	$ 0

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

+ Details

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- Definition

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

+ References

+ Details

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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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