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Loans - Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Average Recorded Investment |  |  |
With no related allowance recorded | $ 18,047 | $ 20,982 | $ 27,868
With an allowance recorded | 3,153 | 605 | 518
Total impaired loans | 21,200 | 21,587 | 28,386
Interest Income Recognized |  |  |
With no related allowance recorded | 45 | 323 | 303
With an allowance recorded | 201 |  | 3
Total impaired loans | 246 | 323 | 306
Commercial |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 120 | 155 | 785
With an allowance recorded |  | 2 | 2
Lease financing receivables |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 272 | 183 |
Real estate - commercial | Owner occupied general purpose |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 1,168 | 2,098 | 4,720
Interest Income Recognized |  |  |
With no related allowance recorded |  | 87 | 82
Real estate - commercial | Owner occupied special purpose |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 364 | 574 | 1,280
Real estate - commercial | Non-owner occupied general purpose |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 1,453 | 1,395 | 2,939
With an allowance recorded | 123 | 123 | 38
Interest Income Recognized |  |  |
With no related allowance recorded |  | 2 | 3
Real estate - commercial | Non-owner occupied special purpose |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 507 | 507 | 712
Real estate - commercial | Retail properties |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 1,130 | 589 |
Real estate - commercial | Farm |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded |  | 636 | 636
Real estate - residential | Investor |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 1,106 | 1,874 | 2,251
With an allowance recorded | 414 |  | 67
Interest Income Recognized |  |  |
With no related allowance recorded |  | 47 | 51
With an allowance recorded | 43 |  |
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 | 7,516 | 10,181 | 10,979
With an allowance recorded | 2,123 | 457 | 68
Interest Income Recognized |  |  |
With no related allowance recorded | 44 | 158 | 160
With an allowance recorded | 123 |  |
Real estate - residential | Revolving and junior liens |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 1,804 | 2,608 | 2,484
With an allowance recorded | 493 | 23 | 208
Interest Income Recognized |  |  |
With no related allowance recorded | 1 | 29 | 7
With an allowance recorded | 35 |  | 3
Consumer |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 4 |  |
Construction Loans | Real estate - commercial | Homebuilder |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded |  |  | 895
Construction Loans | Real estate - commercial | Commercial speculative |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | 37 | 79 | 42
Construction Loans | Real estate - commercial | All other |  |  |
Average Recorded Investment |  |  |
With no related allowance recorded | $ 204 | $ 103 | 145
With an allowance recorded |  |  | $ 135

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- 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 + Details
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