Financial Derivatives (Impact of Fair Value Hedge Accounting on the Carrying Value of Hedged Items) (Details) - Fair value hedges - Designated as Hedging Instruments under GAAP - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Borrowed Funds
Derivative Instruments, Gain (Loss) [Line Items]
Carrying Value of the Hedged Items	$ 37,897	$ 35,139
Cumulative Fair Value Hedge Adjustment included in the Carrying Value of Hedged Items	(181)	(1,057)
Securities available-for-sale
Derivative Instruments, Gain (Loss) [Line Items]
Carrying Value of the Hedged Items	21,753	18,716
Cumulative Fair Value Hedge Adjustment included in the Carrying Value of Hedged Items	$ 206	$ (305)

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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