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Loans and Allowance for Credit Losses - Loans on Nonaccrual Status and Loans Past Due 90 Days or More and Still Accruing (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | $ 22,947 | $ 19,052
End of Period Nonaccrual | 33,209 | 22,947
Nonaccrual With No Related Allowance | 21,359 | 10,516
Interest income recognized on nonaccrual | 188 | 603
Commercial Loans | Commercial real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 6,320 | 7,100
End of Period Nonaccrual | 17,153 | 6,320
Nonaccrual With No Related Allowance | 16,783 | 5,940
Interest income recognized on nonaccrual | 61 | 46
Commercial Loans | Commercial and industrial |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 878 | 283
End of Period Nonaccrual | 612 | 878
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | 0 | 38
Commercial Loans | Commercial construction |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 4,960 | 384
End of Period Nonaccrual | 4,960 | 4,960
Nonaccrual With No Related Allowance | 4,576 | 4,576
Interest income recognized on nonaccrual | 0 | 0
Commercial Loans | Business banking |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 4,147 | 4,490
End of Period Nonaccrual | 3,907 | 4,147
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | 44 | 209
Consumer Loans | Consumer real estate |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 6,312 | 6,526
End of Period Nonaccrual | 6,371 | 6,312
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | 83 | 308
Consumer Loans | Other consumer |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Beginning of Period Nonaccrual | 330 | 269
End of Period Nonaccrual | 206 | 330
Nonaccrual With No Related Allowance | 0 | 0
Interest income recognized on nonaccrual | $ 0 | $ 2

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