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Loans and Loans Held for Sale - Summary of Restructured Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | $ 181 | $ 689 | $ 2,077 | $ 8,513 |
Commercial real estate | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 0 | 0 | 0 |
Commercial and industrial | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 341 | 0 | 5,968 |
Commercial construction | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 0 | 0 | 0 |
Business banking | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 0 | 0 | 1,500 |
Consumer real estate | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 172 | 348 | 2,066 | 1,045 |
Other Consumer | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | $ 9 | $ 0 | 11 | $ 0 |
Total TDRs |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 12,785 |  | $ 31,695
Total TDRs | Commercial real estate | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 480 |  | 1,697
Total TDRs | Commercial and industrial | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 658 |  | 15,637
Total TDRs | Commercial construction | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 1,674 |  | 4,277
Total TDRs | Business banking | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 1,699 |  | 2,554
Total TDRs | Consumer real estate | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 8,260 |  | 7,527
Total TDRs | Other Consumer | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 14 |  | 3
Accruing TDRs |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 8,925 |  | 9,921
Accruing TDRs | Commercial real estate | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 0 |  | 0
Accruing TDRs | Commercial and industrial | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 658 |  | 748
Accruing TDRs | Commercial construction | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 1,674 |  | 2,190
Accruing TDRs | Business banking | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 607 |  | 858
Accruing TDRs | Consumer real estate | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 5,981 |  | 6,122
Accruing TDRs | Other Consumer | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 5 |  | 3
Nonaccruing TDRs |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 3,860 |  | 21,774
Nonaccruing TDRs | Commercial real estate | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 480 |  | 1,697
Nonaccruing TDRs | Commercial and industrial | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 0 |  | 14,889
Nonaccruing TDRs | Commercial construction | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 0 |  | 2,087
Nonaccruing TDRs | Business banking | Commercial Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 1,092 |  | 1,696
Nonaccruing TDRs | Consumer real estate | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 2,279 |  | 1,405
Nonaccruing TDRs | Other Consumer | Consumer Loans |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | $ 9 |  | $ 0

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