Loans and Allowance for Credit Losses - Schedule of Loans by Class Modified as Troubled Debt Restructuring (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2015 USD ($) SecurityLoan	Jun. 30, 2014 USD ($) SecurityLoan
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	58	43
Pre-modification Outstanding Recorded Investment	$ 9,994	$ 11,661
Post-modification Outstanding Recorded Investment	$ 9,994	$ 11,661
Commercial Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	18	13
Pre-modification Outstanding Recorded Investment	$ 5,573	$ 8,833
Post-modification Outstanding Recorded Investment	$ 5,573	$ 8,833
Commercial Real Estate - Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	5	1
Pre-modification Outstanding Recorded Investment	$ 1,162	$ 484
Post-modification Outstanding Recorded Investment	$ 1,162	$ 484
Commercial Real Estate - Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	14	14
Pre-modification Outstanding Recorded Investment	$ 2,159	$ 1,338
Post-modification Outstanding Recorded Investment	$ 2,159	$ 1,338
Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	3	2
Pre-modification Outstanding Recorded Investment	$ 419	$ 175
Post-modification Outstanding Recorded Investment	$ 419	$ 175
Consumer - Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	18	13
Pre-modification Outstanding Recorded Investment	$ 681	$ 831
Post-modification Outstanding Recorded Investment	$ 681	$ 831

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+ References

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- Definition

Post-modification amount of investment in financing receivables 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=35738203&loc=SL6953676-111524

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+ References

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