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Commitments and Off-Balance Sheet Risk (Details Textual) (USD $) In Millions, unless otherwise specified | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2012 | Dec. 31, 2011 | Jun. 30, 2011
Commitments and Off-Balance Sheet Risk (Additional Textual) [Abstract] |  |  |
Reserve or liability balance for financial instruments with off-balance sheet risk | $ 0 |  |
Provision for loan losses expended for financial instruments with off-balance sheet risk | 0.5 | 0.4 |
Loan loss reserve for off balance sheet activities |  | 0.4 |
Notional amount of the underlying interest rate swap agreements entered into by commercial loan customers with correspondent banks | 30.0 |  | 100.0
Net fair value of interest rate swaps entered into by commercial loan customer's with correspondent banks | $ (4.4) |  |
Maximum [Member] |  |  |
Commitments and Off-Balance Sheet Risk (Textual) [Abstract] |  |  |
Fees accreted into income during interest rate swap agreements years | 15 years |  |
Minimum [Member] |  |  |
Commitments and Off-Balance Sheet Risk (Textual) [Abstract] |  |  |
Fees accreted into income during interest rate swap agreements years | 4 years |  |

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- Definition Fees accreted into income during interest rate swap agreements years. + References No definition available. + Details
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- Definition Loan loss reserve for off balance sheet activities. + References No definition available. + Details
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- Definition Reserve or liability balance for financial instruments with off balance sheet risk. + References No definition available. + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13495-108611 + Details
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- Definition Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 + Details
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- Definition Provision charged for the period based on estimated losses to be realized from loan transactions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-DEP -Paragraph 17 -IssueDate 2006-05-01 -Chapter 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 + Details
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