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Loans and Allowance for Credit Losses - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Allowance for credit losses | $ 19,958,000 | $ 22,874,000
Weighted average ratio of loans value to collateral dependent loans value | 59.20% | 59.20%
Collateral Pledged |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | $ 9,204,000 | $ 9,233,000
Allowance for credit losses | 0 | 0
Nonaccrual collateral dependent loans in process of foreclosure | 0 | 0
Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 8,750,000 | 8,757,000
Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 454,000 | 459,000
Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 17,000
Commercial real estate loans | Commercial owner-occupied |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Allowance for credit losses | 2,304,000 | 2,778,000
Commercial real estate loans | Commercial owner-occupied | Collateral Pledged |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 7,147,000 | 7,147,000
Allowance for credit losses | 0 | 0
Commercial real estate loans | Commercial owner-occupied | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 7,147,000 | 7,147,000
Commercial real estate loans | Commercial owner-occupied | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 0
Commercial real estate loans | Commercial owner-occupied | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 0
Commercial real estate loans | Commercial investor-owned |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Allowance for credit losses | 10,856,000 | 12,682,000
Commercial real estate loans | Commercial investor-owned | Collateral Pledged |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 1,603,000 | 1,610,000
Allowance for credit losses | 0 | 0
Commercial real estate loans | Commercial investor-owned | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 1,603,000 | 1,610,000
Commercial real estate loans | Commercial investor-owned | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 0
Commercial real estate loans | Commercial investor-owned | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 0
Residential loans | Home equity |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Allowance for credit losses | 520,000 | 738,000
Residential loans | Home equity | Collateral Pledged |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 454,000 | 459,000
Allowance for credit losses | 0 | 0
Residential loans | Home equity | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 0
Residential loans | Home equity | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 454,000 | 459,000
Residential loans | Home equity | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual | 0 | 0
Consumer loans | Installment and other consumer loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Allowance for credit losses | $ 255,000 | 291,000
Consumer loans | Installment and other consumer loans | Collateral Pledged |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual |  | 17,000
Allowance for credit losses |  | 0
Consumer loans | Installment and other consumer loans | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual |  | 0
Consumer loans | Installment and other consumer loans | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual |  | 0
Consumer loans | Installment and other consumer loans | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Non-accrual |  | $ 17,000

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