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Commitments - Summary of Financial Instrument Commitments (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fixed Letters of Credit [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | $ 685 | $ 910
Fixed Letters of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 685 | 910
Fixed Letters of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] | Financial Standby Letter of Credit [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 329 | 339
Fixed Letters of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 356 | 571
Fixed Letters of Credit [Member] | Unused lines of Credit [Member] |  |
Financial instrument commitments |  |
Loan commitments | 88,883 | 111,348
Variable Letters of Credit [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 13,635 | 15,891
Variable Letters of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 13,568 | 15,824
Variable Letters of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] | Financial Standby Letter of Credit [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 9,051 | 9,612
Variable Letters of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 4,517 | 6,212
Variable Letters of Credit [Member] | Commitments to Extend Credit Nonborrowers [Member] | Performance Guarantee [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 67 | 67
Variable Letters of Credit [Member] | Unused lines of Credit [Member] |  |
Financial instrument commitments |  |
Loan commitments | 316,298 | 320,120
Letter of Credit [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 14,320 | 16,801
Letter of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 14,253 | 16,734
Letter of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] | Financial Standby Letter of Credit [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 9,380 | 9,951
Letter of Credit [Member] | Commitments to Extend Credit to Borrowers [Member] | Performance Guarantee [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 4,873 | 6,783
Letter of Credit [Member] | Commitments to Extend Credit Nonborrowers [Member] | Performance Guarantee [Member] |  |
Financial instrument commitments |  |
Financial instrument commitments | 67 | 67
Letter of Credit [Member] | Unused lines of Credit [Member] |  |
Financial instrument commitments |  |
Loan commitments | $ 405,181 | $ 431,468

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