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Regulatory Matters (Details Textual) (USD $) | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Jun. 30, 2013 | May 31, 2013 | Apr. 30, 2013 | Mar. 31, 2013 | Feb. 28, 2013 | Jan. 31, 2013 | Dec. 31, 2012 | Nov. 30, 2012 | Oct. 31, 2012 | May 31, 2010 | Mar. 31, 2013 | Dec. 31, 2012 | Mar. 31, 2012 | Mar. 31, 2010 | Dec. 31, 2009
Regulatory Matters (Textual) [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Trust preferred securities |  |  |  | $ 32,000,000 |  |  | $ 32,000,000 |  |  |  | $ 32,000,000 | $ 32,000,000 |  |  |
Aggregate amount of restricted core elements allowed in Tier 1 capital |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |
Trusted preferred securities issued date |  |  |  |  |  |  |  |  |  | before May 19, 2010 |  |  |  |  |
Maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier Capital under Dodd-Frank Act |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000,000,000
Cash dividend on common stock |  |  | $ 0.11 |  |  |  |  |  |  |  | $ 0.10 | $ 0.09 | $ 0.00 |  |
Dividend declared date |  |  | Apr. 11, 2013 |  |  | Jan. 10, 2013 |  |  | Oct. 11, 2012 |  |  |  |  |  |
Dividend payable date | Jun. 10, 2013 |  |  | Mar. 08, 2013 |  |  | Dec. 10, 2012 |  |  |  |  |  |  |  |
Dividend payable date of record |  | May 10, 2013 |  |  | Feb. 08, 2013 |  |  | Nov. 09, 2012 |  |  |  |  |  |  |
Dividend suspended date |  |  |  |  |  |  |  |  |  |  |  |  |  | Apr. 01, 2010 |

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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770 + Details
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