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Loans - Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Average Recorded Investment
With no related allowance recorded	$ 11,282	$ 19,105
With an allowance recorded	7,389	926
Total impaired loans	18,671	20,031
Interest Income Recognized
With no related allowance recorded	9	61
With an allowance recorded	59
Total impaired loans	68	61
Commercial
Average Recorded Investment
With no related allowance recorded		132
Lease financing receivables
Average Recorded Investment
With no related allowance recorded	89	425
Real estate - commercial | Owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	417	1,270
With an allowance recorded	152
Real estate - commercial | Owner occupied special purpose
Average Recorded Investment
With no related allowance recorded	391	380
Real estate - commercial | Non-owner occupied general purpose
Average Recorded Investment
With no related allowance recorded	602	1,445
With an allowance recorded		123
Interest Income Recognized
With no related allowance recorded		1
Real estate - commercial | Non-owner occupied special purpose
Average Recorded Investment
With no related allowance recorded		506
With an allowance recorded	1,788
Real estate - commercial | Retail properties
Average Recorded Investment
With no related allowance recorded	541	1,170
Real estate - residential | Investor
Average Recorded Investment
With no related allowance recorded	366	1,744
With an allowance recorded	826
Interest Income Recognized
With no related allowance recorded		12
With an allowance recorded	11
Real estate - residential | Multifamily
Average Recorded Investment
With no related allowance recorded	2,362
Real estate - residential | Owner occupied
Average Recorded Investment
With no related allowance recorded	5,178	9,202
With an allowance recorded	3,559	803
Interest Income Recognized
With no related allowance recorded	9	39
With an allowance recorded	37
Real estate - residential | Revolving and junior liens
Average Recorded Investment
With no related allowance recorded	1,125	2,447
With an allowance recorded	1,064
Interest Income Recognized
With no related allowance recorded		9
With an allowance recorded	11
Consumer
Average Recorded Investment
With no related allowance recorded	12	106
Construction Loans | Real estate - commercial | Commercial speculative
Average Recorded Investment
With no related allowance recorded		72
Construction Loans | Real estate - commercial | All other
Average Recorded Investment
With no related allowance recorded	$ 199	$ 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
-Paragraph 15
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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+ References

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-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

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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+ References

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