Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Short-Term Debt [Line Items]
Federal funds purchased, interest rate	3.91%	3.98%
Federal funds purchased	$ 380,187		$ 586,882
Other short-term borrowings	380,187		586,882
Federal Home Loan Bank borrowings	64,083		64,333
Securities available for sale	958,384		955,584
Collateral loans	1,119,000		1,051,000
Stock of Federal Home Loan Bank	22,787		32,063
Collateral Pledged
Short-Term Debt [Line Items]
Federal funds purchased	$ 444,270		$ 651,220
Federal home loan bank advances, due 2027
Short-Term Debt [Line Items]
Bank Term Funding Program, interest rate	3.87%		4.58%
Federal Home Loan Bank borrowings	$ 40,000		$ 40,000
Federal Home Loan Bank Advances, Due 2030
Short-Term Debt [Line Items]
Bank Term Funding Program, interest rate	4.06%
Federal Home Loan Bank borrowings	$ 24,083		24,333
Federal Funds Purchased
Short-Term Debt [Line Items]
Debt, unused borrowing capacity	175,000		175,000
Federal Funds Purchased \| Collateral Pledged
Short-Term Debt [Line Items]
Debt, unused borrowing capacity	50,000
Securities available for sale	48,170
Federal reserve bank discount window
Short-Term Debt [Line Items]
Debt, unused borrowing capacity	$ 105,110		$ 105,540

Average rate paid on federal funds purchased.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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