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Allowance for Loan Losses - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014
Receivables [Abstract] |  |
Impaired financing receivables | $ 45,650 | $ 43,977
Acquired loans that experienced credit deterioration since acquisition | $ 9,900 |
Minimum period interest and principal of loans past due considered nonperforming (in days) | 90 days |
Evaluation for impairment of substandard and nonaccrual commercial loans | $ 500 |

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- Definition Minimum amount over which evaluation for impairment of substandard and nonaccrual commercial loans are made. + References No definition available. + Details
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- Definition Period interest and principal of loan due treated as loans considered nonperforming. + References No definition available. + Details
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- Definition The recorded amount of loans and debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it was probable, at acquisition, that the investor would be unable to collect all contractually required payments receivable. They are deemed to be impaired since the acquisition and an allowance for credit losses has been recorded. Disclosure is gross of the allowance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5275-111524 + Details
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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524 + Details
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