Derivatives and Hedging Activities - Schedule of Derivative Assets at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loans HFI, net of deferred fees and costs	$ 59,142	$ 58,677
Prepayable Fixed Rate Loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loans HFI, net of deferred fees and costs	3,800	7,200
Loans HFI
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying value of hedged assets	1,802	3,811
Cumulative Fair Value Hedging Adjustment	(26)	0
Investment securities - AFS
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying value of hedged assets	3,482	3,006
Cumulative Fair Value Hedging Adjustment	(41)	(65)
Qualifying debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying Value of Hedged Liabilities	(396)	(396)
Cumulative Fair Value Hedging Adjustment	4	2
Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Portfolio layer method derivative instruments	1,500	3,500
Cumulative basis adjustment	$ (17)	$ 8

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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