Loans - Disaggregated by class of gross loans and type of concession granted (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Payment Delay
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1,566	$ 9
Percentage of Loan Class	0.10%
Payment Delay \| SBA loans \| SBA loans held for investment
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 96	9
Percentage of Loan Class	0.30%
Payment Delay \| Commercial real estate \| Commercial loans
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1,470
Percentage of Loan Class	0.10%
Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 4,736	952
Percentage of Loan Class	0.20%
Term Extension \| Commercial & industrial \| Commercial loans
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1,495	$ 216
Percentage of Loan Class	1.10%	0.20%
Term Extension \| Commercial real estate \| Commercial loans
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		$ 736
Percentage of Loan Class		0.10%
Term Extension \| Residential mortgage loans
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1,036
Percentage of Loan Class	0.20%
Term Extension \| Home equity \| Consumer loans
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 2,205
Percentage of Loan Class	3.20%

Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty.

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