Borrowed Funds (Narrative) (Details) $ in Millions	Mar. 31, 2026 USD ($)
Parent Company \| Senior debt
Debt Instrument [Line Items]
Basis adjustments - Fair value accounting hedges	$ (151)
Parent Company \| Subordinated debt
Debt Instrument [Line Items]
Basis adjustments - Fair value accounting hedges	(40)
Subsidiaries \| Senior debt
Debt Instrument [Line Items]
Basis adjustments - Fair value accounting hedges	(37)
Subsidiaries \| Subordinated debt
Debt Instrument [Line Items]
Basis adjustments - Fair value accounting hedges	$ (73)

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