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Loans and Loans Held for Sale - Restructured Loans By Segment and Type of Concession (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) loan | Sep. 30, 2020 USD ($) loan | Sep. 30, 2021 USD ($) loan | Sep. 30, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 11 | 14 | 29 | 34
Pre-Modification Outstanding Recorded Investment | $ 698 | $ 4,693 | $ 8,919 | $ 13,034
Post-Modification Outstanding Recorded Investment | 689 | 4,561 | 8,513 | 11,585
Bankruptcy |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 317 | 338 | 866 | 1,056
Other |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 80 | 0
Extend Maturity |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 372 | 3,936 | 2,223 | 10,145
Modify Rate |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Modify Payments |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 287 | $ 5,343 | $ 384
Commercial real estate | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 0 | 0 | 0 | 1
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 0 | $ 2,210
Post-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 2,210
Commercial real estate | Bankruptcy | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial real estate | Other | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial real estate | Extend Maturity | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 2,210
Commercial real estate | Modify Rate | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial real estate | Modify Payments | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0
Commercial and industrial | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 2 | 2 | 2 | 3
Pre-Modification Outstanding Recorded Investment | $ 342 | $ 4,021 | $ 6,304 | $ 6,489
Post-Modification Outstanding Recorded Investment | 341 | 4,022 | 5,968 | 5,284
Commercial and industrial | Bankruptcy | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial and industrial | Other | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial and industrial | Extend Maturity | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 341 | 3,735 | 772 | 4,997
Commercial and industrial | Modify Rate | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial and industrial | Modify Payments | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 287 | $ 5,196 | $ 287
Commercial construction | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 0 | 0 | 0 | 3
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 0 | $ 2,592
Post-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 2,561
Commercial construction | Bankruptcy | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial construction | Other | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial construction | Extend Maturity | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 2,561
Commercial construction | Modify Rate | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Commercial construction | Modify Payments | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0
Business banking | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 0 | 1 | 7 | 3
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 333 | $ 1,551 | $ 501
Post-Modification Outstanding Recorded Investment | 0 | 171 | 1,500 | 268
Business banking | Bankruptcy | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Business banking | Other | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 80 | 0
Business banking | Extend Maturity | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 171 | 1,420 | 171
Business banking | Modify Rate | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Business banking | Modify Payments | Commercial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 0 | $ 97
Consumer real estate | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 9 | 10 | 20 | 23
Pre-Modification Outstanding Recorded Investment | $ 356 | $ 334 | $ 1,064 | $ 1,237
Post-Modification Outstanding Recorded Investment | 348 | 364 | 1,045 | 1,258
Consumer real estate | Bankruptcy | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 317 | 334 | 866 | 1,052
Consumer real estate | Other | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 |  | 0
Consumer real estate | Extend Maturity | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 31 | 30 | 31 | 206
Consumer real estate | Modify Rate | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 |  | 0
Consumer real estate | Modify Payments | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 147 | $ 0
Other consumer | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Number of Contracts | loan | 0 | 1 | 0 | 1
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 5 | $ 0 | $ 5
Post-Modification Outstanding Recorded Investment | 0 | 4 | 0 | 4
Other consumer | Bankruptcy | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 4 | 0 | 4
Other consumer | Other | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Other consumer | Extend Maturity | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Other consumer | Modify Rate | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | 0 | 0 | 0 | 0
Other consumer | Modify Payments | Consumer |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 | $ 0 | $ 0

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