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Regulatory Matters (Details Textual) (USD $) | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Feb. 28, 2013 | Jan. 31, 2013 | Nov. 30, 2012 | Oct. 31, 2012 | May 31, 2010 | Mar. 31, 2013 | Mar. 31, 2010 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2009
Regulatory Matters (Textual) [Abstract] |  |  |  |  |  |  |  |  |  |
Maximum amount of dividends distributed by bank to holding company without prior regulatory approval |  |  |  |  |  |  |  | $ 23,000,000 |  |
Cash dividend on common stock |  | $ 0.10 |  | $ 0.09 |  |  |  |  |  |
Dividend declared date |  | Jan. 10, 2013 |  | Oct. 11, 2012 |  |  |  |  |  |
Dividend payable date |  |  |  |  |  | Mar. 08, 2013 |  | Dec. 10, 2012 |  |
Dividend payable date of record | Feb. 08, 2013 |  | Nov. 09, 2012 |  |  |  |  |  |  |
Dividend suspended date |  |  |  |  |  |  | Apr. 01, 2010 |  |  |
Outstanding balance of trust preferred securities |  |  |  |  |  |  |  | 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

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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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- Details
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- Definition The amount of dividends that may be paid or declared in any calendar year without prior approval of regulatory agencies. + 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.(e)) -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 e -Article 4 + Details
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- Definition Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
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