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Loans and Allowance for Credit Losses - Amortized Cost of Loans to Borrowers, Modified (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 12,705 | $ 6,347 | $ 34,651 | $ 22,918
% of Portfolio Segment | 0.17% | 0.08% | 0.45% | 0.30%
Term Extension |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 12,705 | $ 6,347 | $ 22,311 | $ 22,727
Term Extension and Interest Rate Reduction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  | 0 | 191
Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | 0 | 0 | 12,340 | 0
Commercial Loans | Commercial real estate |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 12,482 |  | $ 12,482 | $ 13,505
% of Portfolio Segment | 0.47% |  | 0.47% | 0.52%
Commercial Loans | Commercial real estate | Term Extension |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 12,482 |  | $ 12,482 | $ 13,505
Commercial Loans | Commercial real estate | Term Extension and Interest Rate Reduction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  | 0 | 0
Commercial Loans | Commercial real estate | Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | 0 |  | 0 | 0
Commercial Loans | Commercial and industrial |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  | $ 6,347 | $ 21,839 | $ 6,892
% of Portfolio Segment |  | 0.45% | 1.60% | 0.48%
Commercial Loans | Commercial and industrial | Term Extension |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  | $ 6,347 | $ 9,499 | $ 6,892
Commercial Loans | Commercial and industrial | Term Extension and Interest Rate Reduction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  | 0 | 0
Commercial Loans | Commercial and industrial | Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  | $ 0 | 12,340 | 0
Commercial Loans | Consumer real estate | Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | 0
Commercial Loans | Commercial construction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | $ 1,610
% of Portfolio Segment |  |  |  | 0.43%
Commercial Loans | Commercial construction | Term Extension |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | $ 1,610
Commercial Loans | Commercial construction | Term Extension and Interest Rate Reduction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | 0
Commercial Loans | Commercial construction | Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | 0
Commercial Loans | Business banking | Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | 0
Business Banking |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | $ 658
% of Portfolio Segment |  |  |  | 0.05%
Business Banking | Term Extension |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | $ 658
Business Banking | Term Extension and Interest Rate Reduction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  |  | 0
Consumer Loans | Consumer real estate |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 223 |  | $ 330 | $ 253
% of Portfolio Segment | 0.01% |  | 0.02% | 0.02%
Consumer Loans | Consumer real estate | Term Extension |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 223 |  | $ 330 | $ 62
Consumer Loans | Consumer real estate | Term Extension and Interest Rate Reduction |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period |  |  | 0 | $ 191
Consumer Loans | Consumer real estate | Payment Delays (Other Than Insignificant) |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |
Financing receivable, modified in period | $ 0 |  | $ 0 |

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