Subsequent Event (Additional Information) (Details) (USD $)			9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Subsequent Event [Member] United Commerce [Member]
Subsequent Event [Line Items]
Assets	$ 2,060,122,000	$ 2,006,300,000	$ 120,200,000
Stockholders' Equity Attributable To Parent	185,143,000	185,026,000	13,600,000
Loans and Leases Receivable, Gross	1,284,290,000	1,207,901,000	83,500,000
Deposits			106,500,000
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned			12,700,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares			502,560
Payments to Acquire Businesses, Gross			1,400,000
Business Combination, Consideration Transferred			14,100,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage			4.60%
Payments To Acquire Businesses In Cancellation Of Dilutive Securities			$ 640,000
Business Acquisition Equity Interest Issued Or Issuable Ratio			0.5456
Business Acquisition Cash Consideration Per Share			1.51
Business Combination Consideration Arrangements Description			entitled to receive (a) 0.5456 shares of German American common stock plus (b) a cash payment of $1.51 for each of their former shares of United Commerce common stock and a cash settlement for any fractional shares of German American otherwise issuable to them