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Securities Sold Under Agreements To Repurchase (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Securities sold under agreements to repurchase
Outstanding balance at end of period	$ 68,744,000	$ 64,765,000
Average interest rate at end of period	0.12%	0.13%
Average daily balance during the period	67,762,000	61,930,000
Average interest rate during the period	0.12%	0.25%
Maximum daily balance during the period	$ 76,979,000	$ 81,980,000

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The average effective interest rate during the reporting period.

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The carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase (the identical or substantially the same securities) as a seller-borrower at a specified date for a specified price, also known as a repurchase agreement, or repo. Most repos involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit, are sometimes used in repos.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

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Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of short-term debt outstanding by type or by instrument at that time.

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