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Loans and Allowance for Loan Losses - Impaired loans (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | $ 4,461 | $ 4,717
Loans with related allowance for loan losses, unpaid principal | 4,572 | 4,746
Loans with related allowance for loan losses, Related Allowance | 1,002 | 1,205
Loans with no related allowance for loan losses, Recorded investment | 3,680 | 3,813
Loans with no related allowance for loan losses, unpaid principal | 4,030 | 4,358
Recorded investment | 8,141 | 8,530
Unpaid principal balance | 8,602 | 9,104
Commercial | Commercial and industrial |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 1,606 | 723
Loans with related allowance for loan losses, unpaid principal | 1,689 | 725
Loans with related allowance for loan losses, Related Allowance | 691 | 336
Loans with no related allowance for loan losses, Recorded investment | 1,188 | 1,893
Loans with no related allowance for loan losses, unpaid principal | 1,341 | 2,173
Recorded investment | 2,794 | 2,616
Unpaid principal balance | 3,030 | 2,898
Commercial | Commercial real estate |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 2,791 | 3,948
Loans with related allowance for loan losses, unpaid principal | 2,816 | 3,974
Loans with related allowance for loan losses, Related Allowance | 268 | 837
Loans with no related allowance for loan losses, Recorded investment | 1,885 | 1,276
Loans with no related allowance for loan losses, unpaid principal | 2,029 | 1,415
Recorded investment | 4,676 | 5,224
Unpaid principal balance | 4,845 | 5,389
Consumer | Residential | Real estate first mortgage |  |
Impaired |  |
Loans with no related allowance for loan losses, Recorded investment | 432 | 439
Loans with no related allowance for loan losses, unpaid principal | 461 | 464
Recorded investment | 432 | 439
Unpaid principal balance | 461 | 464
Consumer | Residential | Real estate junior lien |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 27 | 19
Loans with related allowance for loan losses, unpaid principal | 29 | 20
Loans with related allowance for loan losses, Related Allowance | 27 | 19
Loans with no related allowance for loan losses, Recorded investment | 175 | 205
Loans with no related allowance for loan losses, unpaid principal | 199 | 306
Recorded investment | 202 | 224
Unpaid principal balance | 228 | 326
Consumer | Other revolving and installment |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 37 | 27
Loans with related allowance for loan losses, unpaid principal | 38 | 27
Loans with related allowance for loan losses, Related Allowance | 16 | 13
Recorded investment | 37 | 27
Unpaid principal balance | $ 38 | $ 27

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