Derivative Financial Instruments - Additional Information (Detail) - USD ($)	Mar. 31, 2026	Dec. 31, 2025
Derivative [Line Items]
Weighted-average strike rate for outstanding interest rate caps	3.98%
Number of Foreign Currency Derivatives Held	0	0
Approximate credit exposure related to swaps with bank customers	$ 141,000,000.0
Securities Loaned, Fair Value of Collateral	17,800,000
Cash collateral on deposit with other financial institutions	126,000,000.0
Interest rate swaps with upstream financial institution counterparties [Member]
Derivative [Line Items]
Approximate credit exposure related to swaps with bank customers	44,200,000
Designated as Hedging Instrument [Member] \| Financial Institution Counterparties Securities Interest Rate Swaps Assets
Derivative [Line Items]
Forward Contracts – Assets Notional Amount	$ 500,000,000	$ 0
Derivative, Fixed Interest Rate	3.53%

Weighted Average Strike Rate Outstanding Interest Rate Caps

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- Definition

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

+ References

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- Definition

Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

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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- Definition

Number of foreign currency exchange rate derivatives held by the entity at the reporting date.

+ References

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- Definition

Fair value of the securities pledged as collateral against securities loaned.

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