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Allowance for Loan Losses - Information Regarding Loans Modified under TDR (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 Contract | Dec. 31, 2014 USD ($) Contract Contracts
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | Contract | 0 | 1
Pre-modification outstanding recorded investment |  | $ 283
Post-modification outstanding recorded investment |  | $ 344
Real Estate Loans [Member] | Other Real Estate Loans [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | Contracts |  | 1
Pre-modification outstanding recorded investment |  | $ 283
Post-modification outstanding recorded investment |  | $ 344

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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 + Details
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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=49124121&loc=SL6953676-111524 + Details
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