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Loans and Loans Held for Sale - Summary of Restructured Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | $ 1,377 | $ 1,303 | $ 8,159 | $ 7,852 |
Commercial real estate | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 0 | 0 | 2,210 |
Commercial and industrial | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 75 | 6,229 | 2,143 |
Commercial construction | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 0 | 701 | 0 | 2,572 |
Business banking | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 1,130 | 27 | 1,210 | 27 |
Consumer real estate | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | 247 | 500 | 720 | 900 |
Other consumer | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans | $ 0 | $ 0 | 0 | $ 0 |
Total TDRs |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 34,971 |  | $ 46,748
Total TDRs | Commercial real estate | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 6,418 |  | 16,668
Total TDRs | Commercial and industrial | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 14,763 |  | 16,975
Total TDRs | Commercial construction | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 3,222 |  | 3,267
Total TDRs | Business banking | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 2,947 |  | 1,933
Total TDRs | Consumer real estate | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 7,617 |  | 7,900
Total TDRs | Other consumer | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 4 |  | 5
Performing TDRs |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 14,321 |  | 17,460
Performing TDRs | Commercial real estate | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 4 |  | 14
Performing TDRs | Commercial and industrial | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 3,579 |  | 7,090
Performing TDRs | Commercial construction | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 3,222 |  | 3,267
Performing TDRs | Business banking | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 1,439 |  | 1,503
Performing TDRs | Consumer real estate | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 6,073 |  | 5,581
Performing TDRs | Other consumer | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 4 |  | 5
Nonperforming TDRs |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 20,650 |  | 29,288
Nonperforming TDRs | Commercial real estate | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 6,415 |  | 16,654
Nonperforming TDRs | Commercial and industrial | Commercial |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 11,183 |  | 9,885
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 |  |  | 1,508 |  | 430
Nonperforming TDRs | Consumer real estate | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | 1,544 |  | 2,319
Nonperforming TDRs | Other consumer | Consumer |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |
Restructured loans |  |  | $ 0 |  | $ 0

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