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Regulatory Matters (Details Textual) (USD $) | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Oct. 31, 2012 | Jul. 31, 2012 | Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011 | Jul. 03, 2012 | Dec. 31, 2011 | Dec. 31, 2009 | May 15, 2009
Regulatory Matters (Textual) [Abstract] |  |  |  |  |  |  |  |  |  |
Maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier 1 Capital under Dodd-Frank Act |  |  |  |  |  |  |  |  | $ 15,000,000,000 |
Outstanding balance of trust preferred securities |  |  | 32,000,000 |  | 32,000,000 |  |  | 32,000,000 |  |
Aggregate amount of restricted core elements allowed in Tier 1 capital |  |  |  |  | 25.00% |  |  |  |  |
Number of common stock shares available to U.S. Treasury under warrant issued to it on May 15, 2009 |  |  |  |  |  |  |  |  |  | 616,438
Price per share of common stock available to U.S. Treasury under warrant issued to it on May 15, 2009 |  |  |  |  |  |  |  |  |  | 5.11
Repurchase price of warrant |  | 7,500,000 |  |  | 7,465,000 | 0 |  |  |  |
Cash dividend paid by bank to parent company to fund the repurchase of the warrant |  |  | 7,800,000 |  |  |  |  |  |  |
Reduction in retained earnings resulting from repurchase of warrant |  |  |  |  |  |  | $ 7,500,000 |  |  |
Dividend payable date |  | Jul. 02, 2012 |  |  | Dec. 10, 2012 |  |  |  |  |
Dividend declared date | Oct. 11, 2012 |  |  |  |  |  |  |  |  |
Cash dividend on common stock | $ 0.09 |  | $ 0.00 | $ 0.00 | $ 0.00 | $ 0.00 |  |  |  |

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- Definition Maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier 1 Capital under Dodd-Frank Act. + References No definition available. + Details
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- Definition The exercise price of each class of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph i -Subparagraph 4 -Article 4 + Details
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