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Loans - Impaired Loans - Recorded Investment, Unpaid Principal Balance and Related Allowance (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Recorded Investment |  |
With no related allowance recorded | $ 7,708 | $ 14,855
With an allowance recorded | 9,522 | 5,257
Total impaired loans | 17,230 | 20,112
Unpaid Principal Balance |  |
With no related allowance recorded | 9,784 | 17,792
With an allowance recorded | 9,522 | 5,257
Total impaired loans | 19,306 | 23,049
Related Allowance |  |
With an allowance recorded | 588 | 144
Lease financing receivables |  |
Recorded Investment |  |
With no related allowance recorded |  | 178
Unpaid Principal Balance |  |
With no related allowance recorded |  | 213
Real estate - commercial | Owner occupied general purpose |  |
Recorded Investment |  |
With no related allowance recorded | 378 | 455
With an allowance recorded | 305 |
Unpaid Principal Balance |  |
With no related allowance recorded | 421 | 495
With an allowance recorded | 305 |
Related Allowance |  |
With an allowance recorded | 26 |
Real estate - commercial | Owner occupied special purpose |  |
Recorded Investment |  |
With no related allowance recorded | 440 | 342
Unpaid Principal Balance |  |
With no related allowance recorded | 552 | 498
Real estate - commercial | Non-owner occupied general purpose |  |
Recorded Investment |  |
With no related allowance recorded | 42 | 1,163
Unpaid Principal Balance |  |
With no related allowance recorded | 56 | 1,538
Real estate - commercial | Non-owner occupied special purpose |  |
Recorded Investment |  |
With an allowance recorded | 3,575 |
Unpaid Principal Balance |  |
With an allowance recorded | 3,575 |
Related Allowance |  |
With an allowance recorded | 477 |
Real estate - commercial | Retail properties |  |
Recorded Investment |  |
With no related allowance recorded |  | 1,081
Unpaid Principal Balance |  |
With no related allowance recorded |  | 1,177
Real estate - residential | Investor |  |
Recorded Investment |  |
With no related allowance recorded | 361 | 372
With an allowance recorded | 823 | 829
Unpaid Principal Balance |  |
With no related allowance recorded | 531 | 676
With an allowance recorded | 823 | 829
Related Allowance |  |
With an allowance recorded | 10 | 10
Real estate - residential | Multifamily |  |
Recorded Investment |  |
With no related allowance recorded |  | 4,723
Unpaid Principal Balance |  |
With no related allowance recorded |  | 4,965
Real estate - residential | Owner occupied |  |
Recorded Investment |  |
With no related allowance recorded | 5,148 | 5,208
With an allowance recorded | 3,676 | 3,443
Unpaid Principal Balance |  |
With no related allowance recorded | 6,650 | 6,680
With an allowance recorded | 3,676 | 3,443
Related Allowance |  |
With an allowance recorded | 46 | 43
Real estate - residential | Revolving and junior liens |  |
Recorded Investment |  |
With no related allowance recorded | 1,125 | 1,125
With an allowance recorded | 1,143 | 985
Unpaid Principal Balance |  |
With no related allowance recorded | 1,329 | 1,313
With an allowance recorded | 1,143 | 985
Related Allowance |  |
With an allowance recorded | 29 | 91
Consumer |  |
Recorded Investment |  |
With no related allowance recorded | 17 | 7
Unpaid Principal Balance |  |
With no related allowance recorded | 18 | 8
Construction Loans | Real estate - commercial | All other |  |
Recorded Investment |  |
With no related allowance recorded | 197 | 201
Unpaid Principal Balance |  |
With no related allowance recorded | $ 227 | $ 229

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