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Loans and Loans Held for Sale - Restructured Loans for Periods Presented (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | $ 22,650 | $ 32,206
Commercial real estate | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 4,791 | 25,159
Commercial and industrial | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 13,716 | 5,661
Commercial construction | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 2,329 |
Business banking | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 165 |
Consumer real estate | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 1,645 |
Residential mortgage | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 340
Home equity | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 1,037
Other consumer | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 4 |
Performing TDRs |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 17,460 | 36,960
Performing TDRs | Commercial real estate | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 14 | 22,233
Performing TDRs | Commercial and industrial | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 7,090 | 6,909
Performing TDRs | Commercial construction | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 3,267 | 1,425
Performing TDRs | Business banking | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 1,503 |
Performing TDRs | Consumer real estate | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 5,581 |
Performing TDRs | Residential mortgage | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 2,013
Performing TDRs | Home equity | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 4,371
Performing TDRs | Other consumer | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 5 | 9
Nonperforming TDRs |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 29,289 | 8,912
Nonperforming TDRs | Commercial real estate | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 16,654 | 6,713
Nonperforming TDRs | Commercial and industrial | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 9,885 | 695
Nonperforming TDRs | Commercial construction | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 0 | 0
Nonperforming TDRs | Business banking | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 430 |
Nonperforming TDRs | Consumer real estate | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 2,319 |
Nonperforming TDRs | Residential mortgage | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 822
Nonperforming TDRs | Home equity | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 678
Nonperforming TDRs | Other consumer | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 0 | 4
Total TDRs |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 46,748 | 45,872
Total TDRs | Commercial real estate | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 16,668 | 28,946
Total TDRs | Commercial and industrial | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 16,975 | 7,604
Total TDRs | Commercial construction | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 3,267 | 1,425
Total TDRs | Business banking | Commercial |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 1,933 |
Total TDRs | Consumer real estate | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | 7,900 |
Total TDRs | Residential mortgage | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 2,835
Total TDRs | Home equity | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans |  | 5,049
Total TDRs | Other consumer | Consumer |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |
Restructured loans | $ 5 | $ 13

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