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Securities Sold Under Agreements To Repurchase (Details) (USD $)	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Securities sold under agreements to repurchase
Outstanding balance at end of period	$ 57,328,000	$ 64,765,000
Average interest rate at end of period	0.12%	0.13%
Average daily balance during the period	65,632,000	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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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

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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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Weighted average interest rate of short-term debt outstanding.

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