Troubled Debt Restructurings (Details Textual) (USD $)	9 Months Ended	12 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Troubled Debt Restructuring (Textual) [Abstract]
Total troubled debt restructurings	$ 6,900,000	$ 4,300,000
Specific reserves to customers	297,000	48,000
Commitments to lend additional amounts to borrowers classified as troubled debt restructurings	0	0
Maturity period of loans	5 years
Decrease in the allowance for loan losses	161,000
Allowance adjustment charge offs	0
Additional provision or impact to allowance for losses associated with loan	$ 0
Payment default loan period	30 days
Maximum [Member]
Troubled Debt Restructuring (Textual) [Abstract]
Reduction of the notes stated interest rate	1.00%
Maturity period of loans	41 months
Minimum [Member]
Troubled Debt Restructuring (Textual) [Abstract]
Reduction of the notes stated interest rate	3.60%
Maturity period of loans	5 months

Allowance adjustment charge offs.

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- Definition

Financing receivable modification specific reserve to customer.

+ References

No definition available.

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- Definition

Payment default loan period.

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- Definition

Troubled debt restructuring commitment to lend additional amount to borrow.

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- Definition

Troubled debt restructurings, modification of loan terms included reduction of stated interest rate, remaining life.

+ References

No definition available.

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- Definition

Reflects the sum for the period of the additions and reductions to the loan loss reserve, which when added to the opening balance of the reserve will agree to the ending balance in the reserve.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

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-Subparagraph (SX 210.9-03.7(d))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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- Definition

Interest rate stated in the contractual debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Provision charged for the period based on estimated losses to be realized from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 168, 169, 170

-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.

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-Name Regulation S-X (SX)

-Number 210

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-Paragraph 11

-Article 9

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- Definition

For a debtor, the aggregate gain (loss) recognized on the restructuring of payables, after the impact of income tax expense or benefit, arising from the difference between the book value of the debt before the restructuring and the fair value of the payments on the debt after restructuring is complete.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 60

-Section 50

-Paragraph 1

-Subparagraph (b)

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