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Loans - Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Average Recorded Investment
With no related allowance recorded	$ 20,636	$ 21,492
With an allowance recorded	551	513
Total impaired loans	21,187	22,005
Interest Income Recognized
With no related allowance recorded	184	232
With an allowance recorded	2	31
Total impaired loans	186	263
Commercial
Average Recorded Investment
With no related allowance recorded	123	326
With an allowance recorded		2
Lease financing receivables
Average Recorded Investment
With no related allowance recorded	281
Real estate - commercial | Owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	1,169	2,412
Interest Income Recognized
With no related allowance recorded		66
Real estate - commercial | Owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	372	580
Real estate - commercial | Non-owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	1,481	1,655
With an allowance recorded	123	132
Interest Income Recognized
With no related allowance recorded	2	2
With an allowance recorded		31
Real estate - commercial | Non-owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	507	506
Real estate - commercial | Retail properties
Average Recorded Investment
With no related allowance recorded	1,146	990
Real estate - commercial | Farm
Average Recorded Investment
With no related allowance recorded		636
Real estate - residential | Investor
Average Recorded Investment
With no related allowance recorded	1,607	1,864
Interest Income Recognized
With no related allowance recorded	36	35
Real estate - residential | Multifamily
Average Recorded Investment
With no related allowance recorded	2,379
Real estate - residential | Owner occupied
Average Recorded Investment
With no related allowance recorded	8,987	9,916
With an allowance recorded	402	356
Interest Income Recognized
With no related allowance recorded	119	120
Real estate - residential | Revolving and junior liens
Average Recorded Investment
With no related allowance recorded	2,237	2,527
With an allowance recorded	26	23
Interest Income Recognized
With no related allowance recorded	27	9
With an allowance recorded	2
Consumer
Average Recorded Investment
With no related allowance recorded	104
Construction Loans | Real estate - commercial | Commercial speculative
Average Recorded Investment
With no related allowance recorded	37	$ 80
Construction Loans | Real estate - commercial | All other
Average Recorded Investment
With no related allowance recorded	$ 206

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=84173941&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=84173941&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=84173941&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
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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+ References

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-Publisher FASB
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-Topic 310
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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-Publisher FASB
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