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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	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	$ 27,937	$ 22,947
End of Period Nonaccrual	49,618	27,937
Nonaccrual With No Related Allowance	19,678	1,295
Interest income recognized on nonaccrual	824	1,389
Commercial loans | Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	3,228	6,320
End of Period Nonaccrual	25,648	3,228
Nonaccrual With No Related Allowance	10,814	984
Interest income recognized on nonaccrual	92	116
Commercial loans | Commercial and industrial
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	11,173	878
End of Period Nonaccrual	8,979	11,173
Nonaccrual With No Related Allowance	8,864	311
Interest income recognized on nonaccrual	115	85
Commercial loans | Commercial construction
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	0	4,960
End of Period Nonaccrual	869	0
Nonaccrual With No Related Allowance	0	0
Interest income recognized on nonaccrual	25	700
Commercial loans | Business banking
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	2,988	4,147
End of Period Nonaccrual	4,146	2,988
Nonaccrual With No Related Allowance	0	0
Interest income recognized on nonaccrual	146	93
Consumer loans | Consumer real estate
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	10,318	6,312
End of Period Nonaccrual	9,812	10,318
Nonaccrual With No Related Allowance	0	0
Interest income recognized on nonaccrual	443	392
Consumer loans | Other consumer
Financing Receivable, Nonaccrual [Line Items]
Beginning of Period Nonaccrual	230	330
End of Period Nonaccrual	164	230
Nonaccrual With No Related Allowance	0	0
Interest income recognized on nonaccrual	$ 3	$ 3

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