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Loans and Allowance for Credit Losses on Loans - Collateral dependent loans (Details) - USD ($) | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Dec. 31, 2021
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | $ 3,977,814,000 |  | $ 3,820,129,000 |  |  |
Less: allowance for credit losses on loans | 51,729,000 | $ 55,314,000 | 49,480,000 | $ 48,847,000 | $ 45,388,000 | $ 44,281,000
Non accuring loan | 500,000 |  |  |  |  |
Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 55,751,000 |  | 50,478,000 |  |  |
Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 54,733,000 |  | 40,641,000 |  |  |
Accounts Receivable | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 679,000 |  | 5,915,000 |  |  |
Equipment | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 339,000 |  | 1,248,000 |  |  |
Other. | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI |  |  | 2,674,000 |  |  |
Collateral |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 9,390,000 |  | 10,744,000 |  |  |
Commercial |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 10,499,000 | 11,532,000 | 11,968,000 | 13,175,000 | 14,114,000 | 11,751,000
Commercial | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 1,528,000 |  | 7,162,000 |  |  |
Commercial | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 849,000 |  | 883,000 |  |  |
Commercial | Accounts Receivable | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 679,000 |  | 5,915,000 |  |  |
Commercial | Other. | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI |  |  | 364,000 |  |  |
Commercial | Collateral |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 2,000 |  | 569,000 |  |  |
Leases |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 2,592,000 | 2,690,000 | 2,865,000 | 1,534,000 | 1,736,000 | 3,480,000
Leases | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 339,000 |  | 1,248,000 |  |  |
Leases | Equipment | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 339,000 |  | 1,248,000 |  |  |
Leases | Collateral |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 339,000 |  | 1,248,000 |  |  |
Commercial real estate - Investor |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 18,003,000 | 20,031,000 | 10,674,000 | 9,587,000 | 9,436,000 | 10,795,000
Commercial real estate - Investor | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 26,724,000 |  | 16,576,000 |  |  |
Commercial real estate - Investor | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 26,724,000 |  | 16,576,000 |  |  |
Commercial real estate - Investor | Collateral |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 4,848,000 |  | 2,875,000 |  |  |
Commercial real estate - Owner occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 12,385,000 | 12,562,000 | 15,001,000 | 15,171,000 | 11,478,000 | 4,913,000
Commercial real estate - Owner occupied | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 17,636,000 |  | 21,498,000 |  |  |
Commercial real estate - Owner occupied | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 17,636,000 |  | 19,188,000 |  |  |
Commercial real estate - Owner occupied | Other. | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI |  |  | 2,310,000 |  |  |
Commercial real estate - Owner occupied | Collateral |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 4,201,000 |  | 5,808,000 |  |  |
Construction | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 7,206,000 |  |  |  |  |
Construction | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 7,206,000 |  |  |  |  |
Residential real estate - Investor |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 691,000 | 743,000 | 768,000 | 816,000 | 661,000 | 760,000
Residential real estate - Investor | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 32,000 |  | 675,000 |  |  |
Residential real estate - Investor | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 32,000 |  | 675,000 |  |  |
Residential real estate - Owner occupied |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 1,857,000 | 1,868,000 | 2,046,000 | 2,131,000 | 1,869,000 | 2,832,000
Residential real estate - Owner occupied | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 1,679,000 |  | 1,817,000 |  |  |
Residential real estate - Owner occupied | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 1,679,000 |  | 1,817,000 |  |  |
Residential real estate - Owner occupied | Collateral |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans |  |  | 244,000 |  |  |
Multifamily |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 2,572,000 | 2,737,000 | 2,453,000 | 2,530,000 | 2,434,000 | 3,675,000
Multifamily | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 568,000 |  | 1,322,000 |  |  |
Multifamily | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 568,000 |  | 1,322,000 |  |  |
HELOC |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | 1,652,000 | 1,694,000 | 1,806,000 | 1,963,000 | 1,542,000 | 2,510,000
HELOC | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 39,000 |  | 180,000 |  |  |
HELOC | Real Estate | Asset Pledged as Collateral without Right |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Total loans, including deferred loan loan costs and PCI | 39,000 |  | 180,000 |  |  |
Other |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Less: allowance for credit losses on loans | $ 238,000 | $ 278,000 | $ 353,000 | $ 396,000 | $ 583,000 | $ 192,000

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