Borrowings - Other Borrowings (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Finance leases	$ 1,050	$ 1,127
Borrowings	265,390	212,764
Borrower In Custody Program
Debt Instrument [Line Items]
Total borrowing capacity	2,070,119	2,268,599
Federal Reserve Bank \| Commercial and Industrial Loan
Debt Instrument [Line Items]
Deposit liabilities, collateral issued, financial instruments	2,695,429	2,879,586
Other borrowings
Debt Instrument [Line Items]
Borrowings	30,184	29,229
Other borrowings \| Mortgage loans held for sale - guaranteed GNMA repurchase option
Debt Instrument [Line Items]
Borrowings	$ 29,134	$ 28,102

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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