Loans - Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Average Recorded Investment
With no related allowance recorded	$ 30,014	$ 37,289
With an allowance recorded	3,892	8,095
Total impaired loans	33,906	45,384
Interest Income Recognized
With no related allowance recorded	97	93
With an allowance recorded	6	2
Total impaired loans	103	95
Commercial
Average Recorded Investment
With no related allowance recorded	1,699	26
Real estate - commercial \| Owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	4,859	2,567
With an allowance recorded	2,006	926
Interest Income Recognized
With no related allowance recorded	15	1
Real estate - commercial \| Owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	1,476	4,120
With an allowance recorded	304	3,225
Interest Income Recognized
With no related allowance recorded	6
Real estate - commercial \| Non-owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	2,790	6,886
With an allowance recorded	38	469
Interest Income Recognized
With no related allowance recorded		15
Real estate - commercial \| Non-owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	712	652
With an allowance recorded	690
Interest Income Recognized
With an allowance recorded	4
Real estate - commercial \| Retail properties
Average Recorded Investment
With no related allowance recorded		3,107
Real estate - commercial \| Farm
Average Recorded Investment
With no related allowance recorded	685
Real estate - construction \| Homebuilder
Average Recorded Investment
With no related allowance recorded	1,555	1,955
With an allowance recorded		84
Interest Income Recognized
With no related allowance recorded	21	28
Real estate - construction \| Land
Average Recorded Investment
With no related allowance recorded		209
Real estate - construction \| Commercial speculative
Average Recorded Investment
With no related allowance recorded		1,325
With an allowance recorded		588
Real estate - construction \| All other
Average Recorded Investment
With no related allowance recorded	266	150
With an allowance recorded	266	402
Real estate - residential \| Investor
Average Recorded Investment
With no related allowance recorded	2,177	4,673
With an allowance recorded	133	514
Interest Income Recognized
With no related allowance recorded	10	1
Real estate - residential \| Owner occupied
Average Recorded Investment
With no related allowance recorded	11,511	9,589
With an allowance recorded	87	890
Interest Income Recognized
With no related allowance recorded	43	47
With an allowance recorded	1	2
Real estate - residential \| Revolving and junior liens
Average Recorded Investment
With no related allowance recorded	2,284	2,030
With an allowance recorded	368	997
Interest Income Recognized
With no related allowance recorded	2	1
With an allowance recorded	$ 1

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

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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