Loans and Leases (Troubled debt restructured loans with payment default) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013 loans	Jun. 30, 2012 loans	Jun. 30, 2013 loans	Jun. 30, 2012 loans
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	1	0	1	1
Recorded investment for loans with payment defaults	$ 4,670	$ 0	$ 4,670	$ 640
Commercial Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	1	0	1	1
Recorded investment for loans with payment defaults	4,670	0	4,670	640
Agricultural Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	0	0	0	0
Recorded investment for loans with payment defaults	0	0	0	0
Residential Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	0	0	0	0
Recorded investment for loans with payment defaults	0	0	0	0
Consumer Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	0	0	0	0
Recorded investment for loans with payment defaults	0	0	0	0
Commercial | Commercial Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	1	0	1	0
Recorded investment for loans with payment defaults	4,670	0	4,670	0
Commercial Real Estate | Commercial Portfolio Segment
Financing Receivable, Modifications [Line Items]
Number of Loans with payment defaults	0	0	0	1
Recorded investment for loans with payment defaults	$ 0	$ 0	$ 0	$ 640