Loans (Loans Individually Evaluated for Impairment by Class of Loans) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	$ 13,163	[1]		$ 13,163	[1]		$ 15,052	[1]
Recorded Investment	11,276			11,276			12,663
Allowance for Loan Losses Allocated	4,308			4,308			5,411
Average Recorded Investment	13,028		15,752	13,036		16,040
Interest Income Recognized	134		11	188		23
Cash Basis Recognized	173		11	196		21
Impaired Financing Receivables with No Related Allowance [Member] | Commercial and Industrial Loans and Leases [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,975	[1]		1,975	[1]		108	[1]
Recorded Investment	1,995			1,995			87
Allowance for Loan Losses Allocated	0			0			0
Average Recorded Investment	1,993		100	1,052		377
Interest Income Recognized	0		1	0		2
Cash Basis Recognized	0		1	1		2
Impaired Financing Receivables with No Related Allowance [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	3,674	[1]		3,674	[1]		4,312	[1]
Recorded Investment	1,894			1,894			2,154
Allowance for Loan Losses Allocated	0			0			0
Average Recorded Investment	2,196		6,166	2,183		5,858
Interest Income Recognized	0		1	0		5
Cash Basis Recognized	0		1	0		5
Impaired Financing Receivables with No Related Allowance [Member] | Agricultural Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	937	[1]		937	[1]		2,126	[1]
Recorded Investment	946			946			2,137
Allowance for Loan Losses Allocated	0			0			0
Average Recorded Investment	2,041		145	2,231		73
Interest Income Recognized	127		2	175		2
Cash Basis Recognized	168		2	184		2
Impaired Financing Receivables with No Related Allowance [Member] | Subtotal [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	6,586	[1]		6,586	[1]		6,546	[1]
Recorded Investment	4,835			4,835			4,378
Allowance for Loan Losses Allocated	0			0			0
Average Recorded Investment	6,230		6,411	5,466		6,308
Interest Income Recognized	127		4	175		9
Cash Basis Recognized	168		4	185		9
Impaired Financing Receivables with Related Allowance [Member] | Commercial and Industrial Loans and Leases [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	566	[1]		566	[1]		2,642	[1]
Recorded Investment	516			516			2,581
Allowance for Loan Losses Allocated	496			496			1,347
Average Recorded Investment	522		2,795	1,528		2,818
Interest Income Recognized	1		2	2		3
Cash Basis Recognized	1		2	2		3
Impaired Financing Receivables with Related Allowance [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	6,011	[1]		6,011	[1]		5,579	[1]
Recorded Investment	5,925			5,925			5,418
Allowance for Loan Losses Allocated	3,812			3,812			3,914
Average Recorded Investment	6,276		6,546	6,042		6,914
Interest Income Recognized	6		5	11		11
Cash Basis Recognized	4		5	9		9
Impaired Financing Receivables with Related Allowance [Member] | Agricultural Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	[1]		0	[1]		285	[1]
Recorded Investment	0			0			286
Allowance for Loan Losses Allocated	0			0			150
Average Recorded Investment	0		0	0		0
Interest Income Recognized	0		0	0		0
Cash Basis Recognized	0		0	0		0
Impaired Financing Receivables with Related Allowance [Member] | Subtotal [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	6,577	[1]		6,577	[1]		8,506	[1]
Recorded Investment	6,441			6,441			8,285
Allowance for Loan Losses Allocated	4,308			4,308			5,411
Average Recorded Investment	6,798		9,341	7,570		9,732
Interest Income Recognized	7		7	13		14
Cash Basis Recognized	5		7	11		12
Loans Acquired With Deteriorated Credit Quality With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	[1]		0	[1]		45	[1]
Recorded Investment	0			0			25
Allowance for Loan Losses Allocated	0			0			0
Average Recorded Investment	80		1,029	55		212
Interest Income Recognized	0		1	0		1
Cash Basis Recognized	0		1	0		1
Loans Acquired With Deteriorated Credit Quality With Additional Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	439	[1]		439	[1]		155	[1]
Recorded Investment	353			353			118
Allowance for Loan Losses Allocated	150			150			88
Average Recorded Investment	363		205	314		77
Interest Income Recognized	1		0	1		0
Cash Basis Recognized	$ 1		$ 0	$ 1		$ 0

[1] Unpaid Principal Balance is the remaining contractual payments inclusive of partial charge-offs.