Loans - (Impaired Loans - Average Recorded Investment and Interest Income Recognized) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Loans [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 38,647	$ 23,502
Impaired Financing Receivable, Interest Income, Cash Basis Method	863	827
Commercial Loan [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	21,827	5,722
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	414	355
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	893	2,830
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	7	90
Agriculture [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	3,458	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	126	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	158	210
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	0	0
Commercial Construction [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	0	0
Commercial Acquisition/Development [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	1
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	0	0
Multifamily [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	947
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	182
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	0	0
Owner-Occupied [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1,018	1,914
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	51	136
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,166	651
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	40	14
Non Owner-Occupied [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	513
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	33
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,095	634
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	56	28
Total Commercial Real Estate [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	1,018	3,374
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	51	169
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	2,261	1,468
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	96	42
Sr Lien 1-4 Family Closed End [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	605	497
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	7	5
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	6,594	7,455
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	101	110
Jr Lien 1-4 Family Closed End [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	1,568	1,649
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	60	54
Residential Real Estate Segment [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	605	497
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	7	5
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	8,162	9,104
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	161	164
Consumer [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	0	0
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	0	0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	265	297
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	1	2
Impaired Loans With No Related Allowance Recorded [Member] [Member]
Loans [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	26,908	9,593
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method	598	529
Impaired Loans with Related Allowance Recorded [Member]
Loans [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	11,739	13,909
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method	$ 265	$ 298

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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