Loans and Allowance for Loan and Lease Losses - Loans Classified as Troubled Debt Restructuring Payment Concessions (Detail) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($) SecurityLoan	Jun. 30, 2015 SecurityLoan	Jun. 30, 2014 USD ($)
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	2	2
Recorded Balance Before Modification	$ 3,619		$ 3,619
Recorded Balance After Modification	$ 3,619		3,619
Residential Real Estate Loans [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	1	1
Recorded Balance Before Modification	$ 3,311		3,311
Recorded Balance After Modification	$ 3,311		3,311
Commercial Loans and Leases [Member]
Financing Receivable, Modifications [Line Items]
Number \| SecurityLoan	1	1
Recorded Balance Before Modification	$ 308		308
Recorded Balance After Modification	$ 308		$ 308

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.

No definition available.

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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

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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