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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Recorded investment, with no related allowance | $ 5,619 | $ 3,380
Unpaid principal balance, with no related allowance | 6,339 | 4,061
Recorded investment, with related allowance | 9,707 | 10,695
Unpaid principal balance, with related allowance | 10,034 | 11,406
Related allowance | 863 | 1,354
Recorded investment | 15,326 | 14,075
Unpaid principal balance | 16,373 | 15,467
Commercial Loans [Member] |  |
Recorded investment, with related allowance | 8,181 |
Unpaid principal balance, with related allowance | 8,191 |
Related allowance | 672 |
Commercial And Industrial [Member] |  |
Recorded investment, with no related allowance | 1,012 | 207
Unpaid principal balance, with no related allowance | 1,523 | 413
Recorded investment, with related allowance | 1,103 | 2,363
Unpaid principal balance, with related allowance | 1,322 | 3,013
Related allowance | 140 | 667
Recorded investment | 2,115 | 2,570
Unpaid principal balance | 2,845 | 3,426
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Recorded investment, with no related allowance | 1,360 | 1,306
Unpaid principal balance, with no related allowance | 1,481 | 1,462
Recorded investment, with related allowance |  | 664
Unpaid principal balance, with related allowance |  | 715
Related allowance | 51 | 43
Recorded investment | 1,783 | 1,970
Unpaid principal balance | 2,002 | 2,177
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Recorded investment, with no related allowance | 3,245 | 1,867
Unpaid principal balance, with no related allowance | 3,333 | 2,186
Recorded investment, with related allowance |  | 7,666
Unpaid principal balance, with related allowance |  | 7,676
Related allowance | 672 | 643
Recorded investment | 11,426 | 9,533
Unpaid principal balance | 11,524 | 9,862
Consumer Portfolio Segment [Member] |  |
Recorded investment, with no related allowance |  | 2
Unpaid principal balance, with no related allowance |  | 2
Recorded investment, with related allowance | 2 |
Unpaid principal balance, with related allowance | 2 |
Related allowance |  | 1
Recorded investment | 2 | 2
Unpaid principal balance | 2 | $ 2
Real Estate Construction Porfolio Segment [Member] | Residential Loan [Member] |  |
Recorded investment, with related allowance | 423 |
Unpaid principal balance, with related allowance | 521 |
Related allowance | $ 51 |

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- Definition 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524 + Details
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