Borrowings - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Short-term borrowings
Short-term borrowings	$ 76,340	$ 15,900
Net loans	3,956,635	3,951,729
Total investment securities	582,812	606,943
FHLB Advances
Short-term borrowings
Short-term borrowings	2,300,000
Maximum borrowing capacity	1,600,000	1,700,000
Outstanding amount in borrowings	103,800	99,100
Amount of credit facility used to issue standby letters of credit to collateralize public fund deposits	345,900	487,800
Discount Window
Short-term borrowings
Amount of credit facility used to issue standby letters of credit to collateralize public fund deposits	122,800
Assets pledged as collateral \| Borrow in Custody Program
Short-term borrowings
Net loans	414,000
Assets pledged as collateral \| Discount Window
Short-term borrowings
Total investment securities	128,800
Federal Reserve Bank Discount Window
Short-term borrowings
Maximum borrowing capacity	426,800
Bank Term Funding Program
Short-term borrowings
Short-term borrowings	76,300	$ 15,900
Borrow in Custody Program
Short-term borrowings
Amount of credit facility used to issue standby letters of credit to collateralize public fund deposits	$ 304,000

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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