Loans and Leases (Troubled debt in text) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 loans	Mar. 31, 2013 loans	Mar. 31, 2014 Galena State Bank & Trust Co. agreements	Mar. 31, 2014 Galena State Bank & Trust Co. Non-residential Real Estate Losses	Mar. 31, 2014 Galena State Bank & Trust Co. Non-residential Real Estate Recoveries	Mar. 31, 2014 Galena State Bank & Trust Co. Residential Real Estate	Jul. 02, 2009 Elizabeth State Bank	Jul. 02, 2009 Elizabeth State Bank Impaired Purchased Loans	Jul. 02, 2009 Elizabeth State Bank Nonimpaired Purchased Loans
Financing Receivable, Modifications [Line Items]
Number of loans with payment defaults	0	0
Contractually required payments of loans acquired							$ 42.7	$ 13.8	$ 28.9
Estimated fair value of loans acquired							37.8	9.0	28.7
Number of loss share agreements			2
Shared loss arrangement, maximum covered assets			$ 10
Loss sharing agreement, term				5 years	8 years	10 years