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Loans and Allowance for Loan Losses - Impaired loans (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | $ 4,717 | $ 6,362
Loans with related allowance for loan losses, unpaid principal | 4,746 | 6,556
Loans with related allowance for loan losses, Related Allowance | 1,205 | 3,138
Loans with no related allowance for loan losses, Recorded investment | 3,813 | 1,592
Loans with no related allowance for loan losses, unpaid principal | 4,358 | 2,515
Recorded investment | 8,530 | 7,954
Unpaid principal balance | 9,104 | 9,071
Commercial | Commercial and industrial |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 723 | 639
Loans with related allowance for loan losses, unpaid principal | 725 | 727
Loans with related allowance for loan losses, Related Allowance | 336 | 189
Loans with no related allowance for loan losses, Recorded investment | 1,893 | 337
Loans with no related allowance for loan losses, unpaid principal | 2,173 | 1,110
Recorded investment | 2,616 | 976
Unpaid principal balance | 2,898 | 1,837
Commercial | Commercial real estate |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 3,948 | 5,718
Loans with related allowance for loan losses, unpaid principal | 3,974 | 5,823
Loans with related allowance for loan losses, Related Allowance | 837 | 2,946
Loans with no related allowance for loan losses, Recorded investment | 1,276 | 207
Loans with no related allowance for loan losses, unpaid principal | 1,415 | 236
Recorded investment | 5,224 | 5,925
Unpaid principal balance | 5,389 | 6,059
Consumer | Residential | Real estate first mortgage |  |
Impaired |  |
Loans with no related allowance for loan losses, Recorded investment | 439 | 782
Loans with no related allowance for loan losses, unpaid principal | 464 | 797
Recorded investment | 439 | 782
Unpaid principal balance | 464 | 797
Consumer | Residential | Real estate junior lien |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 19 |
Loans with related allowance for loan losses, unpaid principal | 20 |
Loans with related allowance for loan losses, Related Allowance | 19 |
Loans with no related allowance for loan losses, Recorded investment | 205 | 266
Loans with no related allowance for loan losses, unpaid principal | 306 | 372
Recorded investment | 224 | 266
Unpaid principal balance | 326 | 372
Consumer | Other revolving and installment |  |
Impaired |  |
Loans with related allowance for loan losses, Recorded investment | 27 | 5
Loans with related allowance for loan losses, unpaid principal | 27 | 6
Loans with related allowance for loan losses, Related Allowance | 13 | 3
Recorded investment | 27 | 5
Unpaid principal balance | $ 27 | $ 6

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