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Loans - Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Average Recorded Investment
With no related allowance recorded	$ 27,868	$ 35,043	$ 47,877
With an allowance recorded	518	6,185	19,901
Total impaired loans	28,386	41,228	67,778
Interest Income Recognized
With no related allowance recorded	303	467	390
With an allowance recorded	3	1
Total impaired loans	306	468	390
Commercial
Average Recorded Investment
With no related allowance recorded	785	764	112
With an allowance recorded	2		283
Real estate - commercial | Owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	4,720	4,834	3,508
With an allowance recorded		365	872
Interest Income Recognized
With no related allowance recorded	82	104	3
Real estate - commercial | Owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	1,280	2,584	5,275
With an allowance recorded		2,150	4,277
Interest Income Recognized
With no related allowance recorded		45
Real estate - commercial | Non-owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	2,939	5,130	9,892
With an allowance recorded	38	508	1,859
Interest Income Recognized
With no related allowance recorded	3		75
Real estate - commercial | Non-owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	712	1,042	569
Real estate - commercial | Retail properties
Average Recorded Investment
With no related allowance recorded		1,572	5,962
With an allowance recorded			876
Real estate - commercial | Farm
Average Recorded Investment
With no related allowance recorded	636		1,259
Real estate - construction | Homebuilder
Average Recorded Investment
With no related allowance recorded	895	1,903	3,085
With an allowance recorded		84	97
Interest Income Recognized
With no related allowance recorded		82	97
Real estate - construction | Land
Average Recorded Investment
With no related allowance recorded		105	232
Real estate - construction | Commercial speculative
Average Recorded Investment
With no related allowance recorded	42	369	1,501
With an allowance recorded		587	2,748
Real estate - construction | All other
Average Recorded Investment
With no related allowance recorded	145	147	41
With an allowance recorded	135	353	458
Real estate - residential | Investor
Average Recorded Investment
With no related allowance recorded	2,251	4,290	5,576
With an allowance recorded	67	410	2,713
Interest Income Recognized
With no related allowance recorded	51	43
Real estate - residential | Owner occupied
Average Recorded Investment
With no related allowance recorded	10,979	10,299	9,284
With an allowance recorded	68	794	3,737
Interest Income Recognized
With no related allowance recorded	160	187	209
With an allowance recorded		1
Real estate - residential | Revolving and junior liens
Average Recorded Investment
With no related allowance recorded	2,484	2,004	1,570
With an allowance recorded	208	934	1,981
Interest Income Recognized
With no related allowance recorded	7	$ 6	6
With an allowance recorded	$ 3
Consumer
Average Recorded Investment
With no related allowance recorded			$ 11

X

- Definition

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 that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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+ References

Reference 1: 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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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-Topic 310
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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-Publisher FASB
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