Federal Home Loan Bank Borrowings (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Aggregate annual maturities and weighted-average interest rates of Federal Home Loan Bank
Scheduled maturity, 2013	$ 20,536
Scheduled maturity, 2014	16,080
Scheduled maturity, 2015	899
Scheduled maturity, 2016	99
Scheduled maturity, 2017	15,721
Scheduled maturity, 2018 and thereafter	7,432
Scheduled maturity, Total	$ 60,767	$ 111,200
Weighted average rate, 2013	0.55%
Weighted average rate, 2014	3.40%
Weighted average rate, 2015	4.69%
Weighted average rate, 2016	4.35%
Weighted average rate, 2017	3.77%
Weighted average rate, 2018 and thereafter	4.74%
Weighted average rate, Total	2.72%	3.04%

The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Amount of federal home loan bank advances. Advances are loans from the federal home loan bank system to a member (shareholder).

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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Amount of federal home loan bank advances maturing after the fifth fiscal year following the latest fiscal year.

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Amount of federal home loan bank advances maturing in the second fiscal year following the latest fiscal year.

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Amount of federal home loan bank advances maturing in the fourth fiscal year following the latest fiscal year.

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Amount of federal home loan bank advances maturing in the third fiscal year following the latest fiscal year.

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