Investment Securities (Details Textual) (USD $)	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Investment Securities (Additional Textual) [Abstract]
Proceeds from the sale of securities available for sale	$ 0	$ 42,500,000	$ 0	$ 42,527,000
Net gains		1,600,000		1,600,000
Federal Reserve Bank Stock	712,000		712,000
Investment securities pledged	232,337,000		232,337,000		201,207,000
Discount rate			10.00%		11.00%
Voluntary Prepayments			14.20%		16.20%
Conditional Default Rates			9.20%		16.20%
Conditional Default Rates downward after 12 months					9.30%
Conditional Default Rates For 17 yrs after trending downward			0.00%		0.00%
Loss Severity			55.10%		55.50%
Loss Severity related to linear fashion			23.00%		23.00%
Loss Severity related to per year			2.50%		2.50%
Duration period of 16.2% Conditional Default Rates	24 months		24 months		24 months
Duration period of 9.3% Conditional Default Rates	12 months		12 months		12 months
Duration period of zero Conditional Default Rates	17 years		17 years		17 years
Federal Home Loan Bank [Member]
Investment Securities (Textual) [Abstract]
Federal Home Loan Bank Stock	$ 1,585,000		$ 1,585,000
Number of shares owned	15,851		15,851

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Conditional default rates for specified period

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Duration period of 16.2% Conditional Default Rates.

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Duration period of zero Conditional Default Rates.

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Federal home loan bank stock shares.

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Investment securities pledged.

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Loss severity related to linear fashion.

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Voluntary prepayments.

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This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Loss, including interest and principal, incurred on a defaulted security, expressed as a percentage of the original principal balance, used as an input to measure fair value.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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