Long-term Borrowings (Details) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Long-term Borrowings [Abstract]
Percentage of entity's assets equal to line of credit facility (in hundredths)	30.00%
Collateral pledged under blanket floating lien agreement	$ 518,174,000
Debt Instrument [Line Items]
Advance Amount	10,142,000	10,206,000
Weighted Average Rate (in hundredths)	3.01%	3.01%
Valuation allowance, net, related to federal home loan bank, advances	120,000
Public deposit accounts	117,989,000
April 2014 [Member]
Debt Instrument [Line Items]
Due by	Apr. 30, 2014	Apr. 30, 2014
Advance Amount	262,000	337,000
Weighted Average Rate (in hundredths)	3.78%	3.78%
November 2017 [Member]
Debt Instrument [Line Items]
Due by	Nov. 30, 2017	Nov. 30, 2017
Advance Amount	9,880,000	9,869,000
Weighted Average Rate (in hundredths)	2.98%	2.98%
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Collateral for deposits	72,000,000
US government and agency securities [Member]
Debt Instrument [Line Items]
Collateral for deposits	$ 75,824,000

Refers to the percentage of company's assets equal to line of credit facility with federal home loan bank.

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- Definition

Public deposit means to accept fund from public in the form of deposit.

+ References

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- Definition

Refers to the valuation allowance, net, related to federal home loan bank, advances.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 2, 4

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- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

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-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 14

-Subparagraph e

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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- Definition

States the weighted average interest rate applicable to the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

+ References

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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