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Fair Value Measurements, Quantitative Information (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
Impaired Loans Under Range One [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Valuation Technique |  |  | Discounted appraised value
Impaired Loans Under Range One [Member] | Minimum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) |  |  | 0.00%
Impaired Loans Under Range One [Member] | Maximum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) |  |  | 10.00%
Impaired Loans Under Range One [Member] | Weighted Average [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) |  |  | 2.00%
Impaired Loans Under Range Two [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Valuation Technique |  |  | Discounted appraised value
Impaired Loans Under Range Two [Member] | Minimum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount for lack of marketability and age of appraisal (in hundredths) |  |  | 0.00%
Impaired Loans Under Range Two [Member] | Maximum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount for lack of marketability and age of appraisal (in hundredths) |  |  | 60.00%
Impaired Loans Under Range Two [Member] | Weighted Average [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount for lack of marketability and age of appraisal (in hundredths) |  |  | 52.00%
Impaired Loans Under Range Three [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Valuation Technique |  |  | Present value of cash flows
Impaired Loans Under Range Three [Member] | Minimum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount rate (in hundredths) |  |  | 0.00%
Impaired Loans Under Range Three [Member] | Maximum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount rate (in hundredths) |  |  | 7.50%
Impaired Loans Under Range Three [Member] | Weighted Average [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount rate (in hundredths) |  |  | 6.28%
Impaired Loans Under Range Four [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Valuation Technique | Discounted appraised value |  |
Impaired Loans Under Range Four [Member] | Maximum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) | 10.00% | [1] |
Impaired Loans Under Range Five [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Valuation Technique | Present value of cash flows |  |
Impaired Loans Under Range Five [Member] | Minimum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount rate (in hundredths) | 6.25% |  |
Impaired Loans Under Range Five [Member] | Maximum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount rate (in hundredths) | 7.75% |  |
Impaired Loans Under Range Five [Member] | Weighted Average [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Discount rate (in hundredths) | 6.36% |  |
Other Real Estate Owned [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Valuation Technique | Discounted appraised value |  | Discounted appraised value
Other Real Estate Owned [Member] | Minimum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) | 0.00% |  | 0.00%
Discount for lack of marketability and age of appraisal (in hundredths) | 0.00% |  | 0.00%
Other Real Estate Owned [Member] | Maximum [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) | 9.95% |  | 6.00%
Discount for lack of marketability and age of appraisal (in hundredths) | 30.90% |  | 30.90%
Other Real Estate Owned [Member] | Weighted Average [Member] |  |  |
Fair value inputs [Abstract] |  |  |
Selling cost (in hundredths) | 2.28% |  | 4.30%
Discount for lack of marketability and age of appraisal (in hundredths) | 4.94% |  | 4.68%
[1] | Of the Company's impaired loans with specific allocations based on Level 3 inputs, only one loan was valued using fair value of collateral.

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- Definition Refers to the rate of selling cost. + References No definition available. + Details
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- Definition Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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- Definition Description of the inputs and valuation technique(s) used to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 + Details
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