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Loans and Allowance for Credit Losses - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($) | Dec. 31, 2020 | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | $ 9,233,000 |  | $ 226,000
Allowance for Credit Losses | $ 22,874,000 | $ 22,113,000 | 16,677,000
Weighted average ratio of loans value to collateral dependent loans value | 56.00% |  |
Collateral Pledged |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | $ 9,233,000 |  |
Allowance for Credit Losses | 0 |  |
Nonaccrual collateral dependent loans in process of foreclosure | 0 |  |
Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 8,757,000 |  |
Residential Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 459,000 |  |
Other |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 17,000 |  |
Commercial real estate | Commercial real estate, owner-occupied |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 7,147,000 |  | 0
Allowance for Credit Losses | 2,778,000 | 3,135,000 |
Commercial real estate | Commercial real estate, owner-occupied | Collateral Pledged |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 7,147,000 |  |
Allowance for Credit Losses | 0 |  |
Commercial real estate | Commercial real estate, owner-occupied | Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 7,147,000 |  |
Commercial real estate | Commercial real estate, owner-occupied | Residential Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Commercial real estate | Commercial real estate, owner-occupied | Other |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Commercial real estate | Commercial real estate, investor-owned |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 1,610,000 |  | 0
Allowance for Credit Losses | 12,682,000 | 11,624,000 |
Commercial real estate | Commercial real estate, investor-owned | Collateral Pledged |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 1,610,000 |  |
Allowance for Credit Losses | 0 |  |
Commercial real estate | Commercial real estate, investor-owned | Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 1,610,000 |  |
Commercial real estate | Commercial real estate, investor-owned | Residential Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Commercial real estate | Commercial real estate, investor-owned | Other |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Residential loans | Home equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 459,000 |  | 168,000
Allowance for Credit Losses | 738,000 | 1,038,000 |
Residential loans | Home equity | Collateral Pledged |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 459,000 |  |
Allowance for Credit Losses | 0 |  |
Residential loans | Home equity | Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Residential loans | Home equity | Residential Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 459,000 |  |
Residential loans | Home equity | Other |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Consumer loans | Installment and other consumer |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 17,000 |  | $ 58,000
Allowance for Credit Losses | 291,000 | $ 406,000 |
Consumer loans | Installment and other consumer | Collateral Pledged |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 17,000 |  |
Allowance for Credit Losses | 0 |  |
Consumer loans | Installment and other consumer | Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Consumer loans | Installment and other consumer | Residential Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | 0 |  |
Consumer loans | Installment and other consumer | Other |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Non-accrual loans | $ 17,000 |  |

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