Derivative Financial Instruments - Additional Information (Detail) $ in Thousands	Sep. 30, 2026 USD ($) Rate
Derivative [Line Items]
Hedged Asset, Fair Value Hedge, Portfolio Layer Method, Hedged Layer, Amount	$ 500,000
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease)	$ 22,400
Weighted-average strike rate for outstanding interest rate caps	4.10%
Approximate credit exposure related to swaps with bank customers	$ 142,500
Cash collateral on deposit with other financial institutions	84,300
Interest rate swaps with upstream financial institution counterparties [Member]
Derivative [Line Items]
Approximate credit exposure related to swaps with bank customers	616
Cash collateral on deposit with other financial institutions	6,700
Designated as Hedging Instrument [Member] \| Financial Institution Counterparties Securities Interest Rate Swaps Assets
Derivative [Line Items]
Forward Contracts – Assets Notional Amount	$ 500,000
Derivative, Fixed Interest Rate \| 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.

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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.

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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

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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

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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- Definition

Amount of asset hedged in portfolio layer hedging relationship, expected to be remaining at end of hedging relationship.

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