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Loans and Allowance for Credit Losses on Loans - Schedule of Collateral-Dependent Non-Accrual Loans (Details) - USD ($) | Sep. 30, 2022 | Jun. 30, 2022 | Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | --- | --- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ 22,963,000 | $ 22,539,000 | $ 23,023,000 | $ 22,414,000 | $ 19,100,000 | $ 22,874,000
Weighted average ratio of loans value to collateral dependent loans value | 66.00% |  | 67.00% |  |  |
Other residential | Federal Reserve Bank |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Collateral pledged | $ 105,700,000 |  | $ 106,200,000 |  |  |
Federal Home Loan Bank of San Francisco |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Collateral pledged | 1,300,000,000 |  | 1,330,000,000 |  |  |
Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 9,846,000 |  | 7,963,000 |  |  |
Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 699,000 |  | 413,000 |  |  |
Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 92,000 |  | 0 |  |  |
Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 10,637,000 |  | 8,376,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial owner-occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 2,536,000 | 2,617,000 | 2,776,000 | 2,566,000 | 2,037,000 | 2,778,000
Commercial real estate loans | Commercial owner-occupied | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 9,846,000 |  | 7,269,000 |  |  |
Commercial real estate loans | Commercial owner-occupied | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial owner-occupied | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial owner-occupied | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 9,846,000 |  | 7,269,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Commercial real estate loans | Commercial investor-owned |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 12,738,000 | 12,439,000 | 12,739,000 | 12,305,000 | 10,761,000 | 12,682,000
Commercial real estate loans | Commercial investor-owned | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 694,000 |  |  |
Commercial real estate loans | Commercial investor-owned | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 0 |  |  |
Commercial real estate loans | Commercial investor-owned | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 0 |  |  |
Commercial real estate loans | Commercial investor-owned | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans |  |  | 694,000 |  |  |
Allowance for credit losses |  |  | 0 |  |  |
Commercial real estate loans | Installment and other consumer loans | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  |  |  |  |
Commercial real estate loans | Installment and other consumer loans | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  |  |  |  |
Commercial real estate loans | Installment and other consumer loans | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 92,000 |  |  |  |  |
Commercial real estate loans | Installment and other consumer loans | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 92,000 |  |  |  |  |
Allowance for credit losses | 0 |  |  |  |  |
Residential loans | Home equity |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 542,000 | 530,000 | 595,000 | 659,000 | 412,000 | 738,000
Residential loans | Home equity | Commercial Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Residential loans | Home equity | Residential Real Estate |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 699,000 |  | 413,000 |  |  |
Residential loans | Home equity | Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 0 |  | 0 |  |  |
Residential loans | Home equity | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Non-accrual loans | 699,000 |  | 413,000 |  |  |
Allowance for credit losses | 0 |  | 0 |  |  |
Residential loans | Other residential |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Allowance for credit losses | 590,000 | $ 585,000 | 644,000 | $ 623,000 | $ 613,000 | $ 998,000
Residential loans | Other residential | Collateral Pledged |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Nonaccrual collateral dependent loans in process of foreclosure | $ 0 |  | $ 0 |  |  |

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