Variable Interest Entities - Summary of Credit Risk Transfer Agreements (Parenthetical) (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Transfer Of Financial Assets Accounted For As Sales [Line Items]
Deposits securing CRT strips and derivatives liabilities	$ 13.5	$ 46.7

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.

No definition available.

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