Stock Based Compensation (Details) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Options
Balance at beginning of year	174,467	168,266
Shares forfeited	(3,600)
Shares exercised	(2,662)	(20)
Balance at end of year	168,205	168,246
Weighted Average Exercise Price
Exercise price	$ 11.22	$ 11.22
Shares forfeited	$ 12.10
Shares exercised	$ 8.54	$ 8.54
Exercise price	$ 11.22	$ 11.23
Number of options exercisable			12,880
Weighted average exercise price of options exercisable			$ 12.61

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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