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Summary of Significant Accounting Policies (Details) | 3 Months Ended
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Mar. 31, 2013
Summary of Significant Accounting Policies [Abstract] |
Percentage of loan portfolio concentrated in loans secured by real estate (in hundredths) | 87.00%
Discounted percentage for selling and marketing cost (in hundredths) | 10.00%
Income Taxes [Abstract] |
Probability of uncertain tax positions of being realized upon settlement, minimum (in hundredths) | 50.00%
Banking Premises [Member] |
Premises and equipment [Line Items] |
Methods | Straight-Line and Accelerated
Banking Premises [Member] | Minimum [Member] |
Premises and equipment [Line Items] |
Useful lives of the assets | 15 years
Banking Premises [Member] | Maximum [Member] |
Premises and equipment [Line Items] |
Useful lives of the assets | 40 years
Furniture and Equipment [Member] |
Premises and equipment [Line Items] |
Methods | Straight-Line and Accelerated
Furniture and Equipment [Member] | Minimum [Member] |
Premises and equipment [Line Items] |
Useful lives of the assets | 5 years
Furniture and Equipment [Member] | Maximum [Member] |
Premises and equipment [Line Items] |
Useful lives of the assets | 10 years

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