Loans, Leases and Allowance for Credit Losses - Troubled Debt Restructured Loans by Class for Which There was Payment Default (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) SecurityLoan	Mar. 31, 2015 USD ($) SecurityLoan
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	1	1
Recorded Investment \| $	$ 5,381	$ 137
Commercial real estate [Member] \| Multi-family [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0
Commercial real estate [Member] \| Non-owner occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	1	0
Recorded Investment \| $	$ 5,381	$ 0
Commercial real estate [Member] \| Owner occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0
Commercial and industrial [Member] \| Leases [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0
Commercial and industrial [Member] \| Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0
Construction and land development [Member] \| Land [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0
Construction and land development [Member] \| Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	1
Recorded Investment \| $	$ 0	$ 137
Residential real estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| SecurityLoan	0	0
Recorded Investment \| $	$ 0	$ 0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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