| Loans - Troubled Debt Restructurings that Defaulted Subsequent to Modifications Occurring Within Previous Twelve Months, Disaggregated by Loan Class (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
| Sep. 30, 2016  USD ($)  SecurityLoan | Sep. 30, 2015  USD ($)  SecurityLoan | Sep. 30, 2016  USD ($)  SecurityLoan | Sep. 30, 2015  USD ($)  SecurityLoan | |
| Financing Receivable, Modifications [Line Items] | ||||
| Number of Loans | SecurityLoan | 1 | 1 | 1 | 1 | 
| Recorded Investment | $ | $ 53 | $ 466 | $ 53 | $ 466 | 
| Real estate loans [Member] | Hospitality [Member] | ||||
| Financing Receivable, Modifications [Line Items] | ||||
| Number of Loans | SecurityLoan | 0 | 1 | 0 | 1 | 
| Recorded Investment | $ | $ 0 | $ 466 | $ 0 | $ 466 | 
| Commercial and industrial loans [Member] | Commercial term [Member] | ||||
| Financing Receivable, Modifications [Line Items] | ||||
| Number of Loans | SecurityLoan | 1 | 0 | 1 | 0 | 
| Recorded Investment | $ | $ 53 | $ 0 | $ 53 | $ 0 | 
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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. No definition available. 
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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