Short-Term Borrowings (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Secured Debt, Repurchase Agreements
Carrying amount of securities sold under repurchase agreements with customers	$ 299,600	$ 311,400
Carrying amount of the securities pledged to collateralize repurchase agreements	8,908,521	8,715,214
Federal funds purchased	343,758	306,841
Loans held for investment, net of allowance for credit losses	48,910,901	48,013,330
FRB Borrowings
Secured Debt, Repurchase Agreements
Debt Instrument Collateral Amount	11,400,000
Letter of credit outstanding	0	0
Maximum borrowing capacity	11,400,000
Loans held for investment, net of allowance for credit losses	15,000,000
FHLB Advances
Secured Debt, Repurchase Agreements
Secured collateral	17,800
Unused net credit available with the FHLB	5,700
FHLB Advances
Secured Debt, Repurchase Agreements
Outstanding advances	0	0
Debt Instrument Collateral Amount	5,700,000
Amount of cash pledged as collateral	22,200
Debt Instrument Unused Borrowing Capacity Amount	$ 5,700,000
Asset Pledged as Collateral \| FRB Borrowings
Secured Debt, Repurchase Agreements
Financing Receivable, Pledging Purpose [Extensible Enumeration]	Federal funds purchased
Asset Pledged as Collateral \| FHLB Advances
Secured Debt, Repurchase Agreements
Debt Instrument Collateral Amount	$ 9,000,000
Amount of cash pledged as collateral	30,100
Asset Pledged as Collateral \| Securities sold under agreements to repurchase
Secured Debt, Repurchase Agreements
Carrying amount of the securities pledged to collateralize repurchase agreements	$ 351,200	$ 331,500

The amount of cash pledged as collateral.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB), refers to the amount of collateral currently required or utilized to secure obligations with the FHLB.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of assets pledged to secure a debt instrument.

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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 advances or credit lines available from the Federal Home Loan Bank (FHLB).

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

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Indicates pledging purpose of financing receivable.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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