Loans (Schedule of Aging of Recorded Investment in Past Due Loans) (Details) - USD ($) $ in Thousands	Jun. 30, 2015		Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	$ 1,481,885	[1],[2]	$ 1,457,768	[3],[4]
Loans Past Due	6,261	[2]	6,942	[3]
Loans Not Past Due	1,475,624	[2]	1,450,826	[3]
Accrued interest	5,417		5,778
Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	397,753	[1]	380,851	[4]
Loans Past Due	661		776
Loans Not Past Due	397,092		380,075
Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	585,723	[1]	584,426	[4]
Loans Past Due	1,390		1,267
Loans Not Past Due	584,333		583,159
Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	224,591	[1]	219,640	[4]
Loans Past Due	31		100
Loans Not Past Due	224,560		219,540
Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	88,639	[1]	86,570	[4]
Loans Past Due	621		469
Loans Not Past Due	88,018		86,101
Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	47,700	[1]	48,732	[4]
Loans Past Due	219		235
Loans Not Past Due	47,481		48,497
Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	137,479	[1]	137,549	[4]
Loans Past Due	3,339		4,095
Loans Not Past Due	134,140		133,454
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	2,538	[2]	3,532	[3]
30-59 Days Past Due | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	252		628
30-59 Days Past Due | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	169		504
30-59 Days Past Due | Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	31		25
30-59 Days Past Due | Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	218		197
30-59 Days Past Due | Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	99		132
30-59 Days Past Due | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,769		2,046
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	759	[2]	371	[3]
60-89 Days Past Due | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	69		0
60-89 Days Past Due | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	249		10
60-89 Days Past Due | Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	0		0
60-89 Days Past Due | Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	97		4
60-89 Days Past Due | Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	45		28
60-89 Days Past Due | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	299		329
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	2,964	[2]	3,039	[3]
90 Days or More Past Due | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	340		148
90 Days or More Past Due | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	972		753
90 Days or More Past Due | Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	0		75
90 Days or More Past Due | Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	306		268
90 Days or More Past Due | Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	75		75
90 Days or More Past Due | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,271		1,720
Receivables Acquired with Deteriorated Credit Quality | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	7,217		8,361
Loans Past Due	0		648
Loans Not Past Due	7,217		7,713
Receivables Acquired with Deteriorated Credit Quality | 30-59 Days Past Due | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	0		0
Receivables Acquired with Deteriorated Credit Quality | 60-89 Days Past Due | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	0		0
Receivables Acquired with Deteriorated Credit Quality | 90 Days or More Past Due | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	$ 0		$ 648

[1] Total recorded investment in loans includes $5,417 in accrued interest.

[2] Total recorded investment in loans includes $5,417 in accrued interest.

[3] Total recorded investment in loans includes $5,778 in accrued interest.

[4] Total recorded investment in loans includes $5,778 in accrued interest.