Participation in the Small Business Lending Fund (SBLF) of the U.S. Treasury Department (U.S. Treasury) and Repurchase of Shares Issued Under the Troubled Asset Relief Program (TARP) (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Non-Cumulative Perpetual Series B Preferred Stock Issued, Shares Pursuant To U.S. Treasury's Small Business Lending Fund Program (in shares)		10,000
Non-Cumulative Perpetual Series B Preferred Stock Issued Pursuant To U.S. Treasury's Small Business Lending Fund Program, Liquidation Preference (in dollars per share)		$ 1,000
Proceeds From Issuance Of Non-Cumulative Perpetual Preferred Series B Preferred Stock Pursuant To U.S. Treasury'S Small Business Lending Fund Program		$ 10,000,000
Preferred Stock Terms Of Issuance		The issuance was pursuant to the U.S. Treasury's SBLF program, a $30.0 billion fund established under the Small Business Jobs Act of 2010, which encourages lending to small businesses by providing capital to qualified community banks with assets less than $10.0 billion.
Preferred Stock, Dividend Payment Rate, Variable		The dividend rate, which is calculated on the aggregate liquidation amount, has been initially set at 5% per annum based upon the current level of Qualified Small Business Lending (QSBL) by the Bank. The dividend rate for future periods will be set based upon the percentage change in qualified lending between each dividend period and the baseline QSBL level established at the time the Agreement was entered into. Such dividend rate may vary from 1% per annum to 5% per annum for the second through tenth dividend periods, and from 1% per annum to 7% per annum for the eleventh through the eighteenth dividend periods. If the Series B Preferred Stock remains outstanding for more than four-and-one-half years, the dividend rate will be fixed at 9%.
Preferred Stock, Redemption Terms		The Corporation may redeem the shares of Series B Preferred Stock, in whole or in part, at any time at a redemption price equal to the sum of the liquidation amount and the per-share amount of any unpaid dividends for the then-current period, subject to any required prior approval by the Corporation's primary federal banking regulator. If paid in part, payments are required to be at least 25% of the original proceeds.
Repurchase Of Number Of Fixed Rate Cumulative Perpetual Preferred Stock, Series A Issued In Association With Participation In Tarp (in shares)		7,500
Liquidation Preference Value Of Fixed Rate Cumulative Perpetual Preferred Stock, Series A Issued In Association With Participation In TARP (in dollars per share)		$ 1,000
Repurchased Value Of Fixed Rate Cumulative Perpetual Preferred Stock, Series A Issued In Association With Participation In Tarp		7,500,000
Number Of Common Stock, Shares Issuable To U.S. Treasury Upon Conversion Of Warrants (in shares)		50,111
Par Value Of Common Stock Issuable To U.S. Treasury Upon Conversion Of Warrants (in dollars per share)		$ 1.25
Remaining Term Of Warrants Issued To U.S. Treasury To Purchase Common Stock		10 years
Exercise Price Of Warrants Issued To U.S. Treasury To Purchase Common Stock (in dollars per share)		$ 22.45
Payments for Repurchase of Warrants	$ 0	$ 51,000