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Loans and Allowance for Credit Losses on Loans (Additional Information) (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 USD ($) loan | Dec. 31, 2020 USD ($) loan | Dec. 31, 2019 USD ($) loan | Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
SBA PPP Loans, Total Originations, Number of Contracts | loan | 1,620 | 3,034 |  |
SB PPP Loans, Total Originations | $ 102,200,000 | $ 244,800,000 |  |
Loans and Leases Receivable, Related Parties, Description | At December 31, 2021 and 2020, outstanding loans to certain officers, directors and their associated companies were less than 5% of the Company's shareholders' equity. | At December 31, 2021 and 2020, outstanding loans to certain officers, directors and their associated companies were less than 5% of the Company's shareholders' equity. |  |
Number of Portfolio Concentration Industries | 0 |  |  |
Foregone interest | $ 256,000 | $ 335,000 | $ 420,000 |
Loans and Leases Receivable, Impaired, Commitment to Lend | $ 0 |  |  |
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | loan | 0 | 0 | 0 |
Allowance Related to Troubled Debt Restructurings assigned during period | $ 6,000 | $ 0 | $ 15,000 |
Loans and Leases Receivable, Deferred Income | 3,110,000 | 856,000 |  |
Financing Receivable, Allowance for Credit Losses | 33,256,000 | 37,865,000 | 25,171,000 | $ 24,712,000
Loans and Leases Receivable, Excluded Accrued Interest from Amortized Cost | $ 7,800,000 | 10,200,000 |  |
SBA PPP Loans, 2021 Originations, Number of Contracts Outstanding | loan | 379 |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | $ 1,099,415,000 | 716,230,000 |  |
SBA PPP Loans, 2020 Originations, Number of Contracts Outstanding | loan | 37 |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | $ 557,853,000 | 527,204,000 |  |
Temporary Loan Modifications, COVID-Related Loan Modification, Recorded Investment | 0 | 26,500,000 |  |
Non-Accrual Loans | 4,327,000 | 7,596,000 |  |
Allowance for Loan and Lease Losses, Period Increase (Decrease) | 4,600,000 |  |  |
Small Business Administration, CARES Act |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non-Accrual Loans | 1,200,000 | 1,000,000 |  |
Small Business Administration, CARES Act | Financial Asset, 30 to 89 Days Past Due |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Financing Receivable, before Allowance for Credit Loss | 410,000 | 310,000 |  |
Residential real estate |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Financing Receivable in Process of Foreclosure | 888,000 | 1,500,000 |  |
Financing Receivable, Allowance for Credit Losses | 6,133,000 | 3,474,000 | 5,842,000 | 6,071,000
Non-Accrual Loans | 2,107,000 | 3,477,000 |  |
Loans Receivable [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Performing TDRs | 2,400,000 | 2,800,000 |  |
Non-Performing TDRs | 394,000 | 248,000 |  |
Consumer |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Financing Receivable, Allowance for Credit Losses | 79,000 | 393,000 | $ 507,000 | $ 234,000
Non-Accrual Loans | 32,000 | 4,000 |  |
SBA PPP Portfolio Segment |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans and Leases Receivable, Deferred Income | 1,200,000 | 2,200,000 |  |
Financing Receivable, Allowance for Credit Losses | $ 19,000 | 69,000 |  |
Total Loan Portfolio [Member] | Loan Concentration Risk [Member] | Non-Residential Building Operators Industry Sector [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Concentration Risk, Percentage | 14.00% |  |  |
Commercial real estate | Loan Concentration Risk [Member] | Non-Residential Building Operators Industry Sector [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Concentration Risk, Percentage | 32.00% |  |  |
Commercial |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | $ 91,247,000 | 54,153,000 |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 44,213,000 | 73,897,000 |  |
SBA PPP Portfolio Segment |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 35,634,000 | 135,095,000 |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | $ 319,000 | $ 0 |  |

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