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Securities - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2013 Contract | Dec. 31, 2012 Contract | Dec. 31, 2011
Amortized Cost And Fair Value Debt Securities [Abstract] |  |  |
Number of U.S. agency and mortgage-backed securities | 40 | 12 |
Number of obligations of state and political subdivisions in an unrealized loss position | 21 | 9 |
Percentage of investment portfolio | 100.00% |  |
Weighted-average period of re-pricing of portfolio | 4 years 6 months | 3 years 7 months 6 days |
Proceeds from maturities, calls, and principal payments of securities available for sale | $ 4,600,000 | $ 36,300,000 | $ 14,900,000
Gross realized gains on securities available for sale | 0 | 1,300,000 | 65,000
Gross realized losses on securities available for sale | 0 | 0 | 6,000
Securities book value | 3,100,000 | 24,000,000 |
Impairment recognized | $ 0 |  |

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- Definition Impairment losses related to federal home loan stock. + References No definition available. + Details
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- Definition This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 + Details
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- Definition The carrying amount of securities categorized neither as held-to-maturity nor trading which serve as security for borrowings or other arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 6 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph b -Article 4 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX210.4-08(b)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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