Short-Term Borrowings and Long-Term Debt - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Sep. 30, 2024
Debt Instrument [Line Items]
FHLB advances borrowing capacity		$ 8,900
Repayments of borrowing	$ 4,500
Junior Subordinated Debt
Debt Instrument [Line Items]
Repayments of subordinated debt	$ 117

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