Derivatives and Hedging Activities (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Margin on interest rate swap not netted	$ 756	$ 368
Hedged Liability, Statement of Financial Position [Extensible Enumeration]	Outstanding balance	Outstanding balance
Carrying values of hedged liabilities	$ 37,000	$ 18,900
Cumulative amount of fair value hedging adjustments	366	27
Increase (decrease) in interest expense on long term debt and other	106	254	$ 189
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount of derivatives	39,000	28,800
Other Expense
Derivatives, Fair Value [Line Items]
Gain (loss) in changes in fair value of derivatives not designated as hedges	121	102	82
Credit Valuation Adjustment
Derivatives, Fair Value [Line Items]
Derivative, amount of hedged item	0	0
Fair Value Hedges | Fixed-Rate Debt Obligations
Derivatives, Fair Value [Line Items]
Derivative, amount of hedged item	36,700	18,900
Net Investment Hedges
Derivatives, Fair Value [Line Items]
Notional amount of derivatives	16,300	14,300
Gain (loss) on net investment hedges, net of taxes	(1,000)	800	(600)
Reclassifications out of AOCI	0	0	0
Embedded Derivative | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Notional amount of derivatives	78	78
Fair value of embedded derivative asset, gross	10	31
Embedded Derivative | Noninterest Income | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Gain (loss) on embedded derivative	$ (21)	$ 13	$ (9)