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Loans and Allowance for Loan Losses - Additional Information (Detail) (USD $) | 9 Months Ended
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Sep. 30, 2013 SecurityLoan | Sep. 30, 2012
Receivables [Abstract] |  |
Percentage of loans secured by real estate | 60.00% |
Interest income recognized | $ 1,300,000 | $ 1,000,000
Troubled debt restructuring principal deferral | 1 |
Interest income on impaired loans | $ 0 | $ 0

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- Definition Percentage Of Loans Secured By Real Estate + References No definition available. + Details
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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=28368275&loc=SL6953676-111524 + Details
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- Definition Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524 + Details
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- Definition Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554 + Details
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- Details
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