Loans Loans (Schedule of Contractually Required Payments on Acquired Loans) (Details) - Loans Acquired with Deteriorated Credit Quality - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	$ 14,094	$ 0
Cash Flows Expected to be Collected at Acquisition	11,051	0
Fair Value of Acquired Loans at Acquisition	8,807	0
Commercial and Industrial Loans
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	220	0
Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	10,612	0
Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	896	0
Home Equity Loans
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	0	0
Consumer Loans
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	87	0
Residential Mortgage Loans
Financing Receivable, Recorded Investment [Line Items]
Contractually required payments on loans acquired with evidence of deteriorated credit quality	$ 2,279	$ 0

Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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- Definition

Amount of contractually required payments receivable at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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