Investment Securities - Schedule of Company Holding Shares of FHLB-NY Stock and FHLB-Indianapolis Stock (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Schedule of Investments [Line Items]
Federal home loan bank stock	$ 1,018	$ 1,146
Federal Reserve Bank stock	221	219
FHLB-Indianapolis
Schedule of Investments [Line Items]
Federal home loan bank stock	255	329
FHLB-New York
Schedule of Investments [Line Items]
Federal home loan bank stock	$ 542	$ 598

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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