Loans - Summary of Interest Foregone on Impaired Loans (Detail) - USD ($) $ in Thousands  | 
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015  | 
Sep. 30, 2014  | 
Sep. 30, 2015  | 
Sep. 30, 2014  | 
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| Receivables [Abstract] | ||||
| Interest income that would have been recognized had impaired loans performed in accordance with their original terms | $ 1,444 | $ 1,063 | $ 3,361 | $ 3,490 | 
| Less: Interest income recognized on impaired loans | (643) | (796) | (2,153) | (2,353) | 
| Interest foregone on impaired loans | $ 801 | $ 267 | $ 1,208 | $ 1,137 | 
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- Definition Loans and leases receivable impaired interest income forgone. No definition available. 
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- Definition Loans and leases receivable impaired interest income not recognized. No definition available. 
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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