Borrowings - Narrative (Detail) - USD ($) $ in Billions	Jun. 30, 2023	Dec. 31, 2022
Federal Funds Purchased
Debt Instrument [Line Items]
Aggregate availability under federal funds line	$ 1.7	$ 1.7

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.

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+ Details