Allowance for Credit Losses, Loan Portfolio Allocated by Management's Internal Credit Ratings (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	$ 1,712,244	$ 1,388,236
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	491,903	407,514
Agricultural Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	357,207	328,264
Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	96,519	41,092
Residential 1st Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	171,880	151,292
Home Equity Lines and Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	33,017	35,477
Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	281,963	256,414
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	230,819	150,398
Consumer & Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	4,719	5,052
Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	44,217	12,733
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	1,678,690	1,353,440
Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	483,146	398,488
Pass [Member] | Agricultural Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	357,207	325,926
Pass [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	94,887	39,460
Pass [Member] | Residential 1st Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	170,462	149,798
Pass [Member] | Home Equity Lines and Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	32,054	34,821
Pass [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	281,232	255,443
Pass [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	211,036	132,008
Pass [Member] | Consumer & Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	4,449	4,763
Pass [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	44,217	12,733
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	29,934	29,038
Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	8,651	7,979
Special Mention [Member] | Agricultural Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	2,338
Special Mention [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	1,632	1,632
Special Mention [Member] | Residential 1st Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	744	774
Special Mention [Member] | Home Equity Lines and Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	85	0
Special Mention [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	679	889
Special Mention [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	18,143	15,426
Special Mention [Member] | Consumer & Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	0
Special Mention [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	0
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	3,620	5,758
Substandard [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	106	1,047
Substandard [Member] | Agricultural Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	0
Substandard [Member] | Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	0
Substandard [Member] | Residential 1st Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	674	720
Substandard [Member] | Home Equity Lines and Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	878	656
Substandard [Member] | Agricultural [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	52	82
Substandard [Member] | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	1,640	2,964
Substandard [Member] | Consumer & Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	270	289
Substandard [Member] | Leases [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	0
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	0	0
Loss [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans & Leases	$ 0	$ 0