Loans - Restructured in Troubled Debt (Detail) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015 USD ($) Loans	Dec. 31, 2014 USD ($) Loans
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loans	15	15
Loan Balance	$ 13,941	$ 18,658
Specific Reserve	$ 2,898	$ 2,670
Commercial, Industrial, and Agricultural [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loans	7	7
Loan Balance	$ 3,878	$ 3,920
Specific Reserve	$ 960	$ 179
Commercial Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loans	8	8
Loan Balance	$ 10,063	$ 14,738
Specific Reserve	$ 1,938	$ 2,491
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loans	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loans	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0
Credit Cards [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loans	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0

Financing receivable modifications specific reserve.

No definition available.

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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.

+ Details

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- Definition

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=49124121&loc=SL6953676-111524

+ Details

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- Definition

The amount of the outstanding recorded investment related to 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 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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