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U.S.Treasury Capital Purchase Program Participation - Additional Information (Detail) (USD $) | 0 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
May 15, 2009 | Sep. 30, 2012 | Jun. 30, 2012 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Class of Warrant or Right [Line Items] |  |  |  |  |  |
Sale of preferred stock and a warrant for common stock | $ 21,000,000 |  |  |  |  |
Number of cumulative perpetual preferred stock shares | 21,000 |  |  |  |  |
Liquidation value of cumulative perpetual preferred stock | $ 1,000 |  |  |  |  |
Number of common stock shares available to U.S. Treasury under warrant issued | 616,438 |  |  |  |  |
Preferred stock, par value |  |  |  |  |  |
Rate of cumulative dividends for the first five years | 5.00% |  |  |  |  |
Rate of cumulative dividends for the remaining period | 9.00% |  |  |  |  |
Period of common stock warrant |  |  |  | 10 years |  |
Exercise price of common stock warrant | 5.11 |  |  |  |  |
Discount rate | 12.00% |  |  |  |  |
Estimated fair value | 15,500,000 |  |  |  |  |
Fair value of common stock warrant | 900,000 |  |  |  |  |
Aggregate fair value for preferred stock and the common stock warrant | 16,400,000 |  |  |  |  |
Aggregate attributable to the preferred stock | 94.60% |  |  |  |  |
Aggregate attributable to the common stock warrants | 5.40% |  |  |  |  |
Issuance amount allocated to preferred stock | 19,900,000 |  |  |  |  |
Issuance amount allocated to common stock warrant | 1,100,000 |  |  |  |  |
Discount on the preferred stock | 1,300,000 |  |  |  |  |
Period of reduction in net income available to common shareholders | 5 years |  |  |  |  |
Reduction from retained earnings resulting from accelerated discount on preferred Stock |  |  | 600,000 |  |  |
Reduction in shareholders' equity resulting from repurchase of warrant |  | 7,500,000 |  |  |  |
Repurchase price of warrant |  |  |  | 0 | 7,465,000 | 0
Minimum [Member] |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |
Reduction in net income attributable to common shareholders due to accretion of preferred stock discount | 200,000 |  |  |  |  |
Maximum [Member] |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |
Reduction in net income attributable to common shareholders due to accretion of preferred stock discount | 300,000 |  |  |  |  |
Stock warrant [Member] |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |
Expected dividend yield | 1.00% |  |  |  |  |
Risk-free interest rate | 1.99% |  |  |  |  |
Expected life | 5 years |  |  |  |  |
Expected volatility | 53.00% |  |  |  |  |
Weighted average fair value | $ 3.92 |  |  |  |  |
Repurchase price of warrant |  | 7,500,000 |  |  |  |
Preferred Stock [Member] |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |
Direct cost associated with transaction | 200,000 |  |  |  |  |
Repurchase of Preferred Stock |  |  | $ 21,000,000 |  |  |

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