Derivatives - Schedule of Gains/(Losses) on Derivatives Associated with Interest Rate Risk Management Activities (Details) - Customer Interest Rate Contracts Hedging - Hedging Instruments And Hedged Items - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Customer interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses)	$ 220	$ 10	$ 195
Offsetting upstream interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses)	$ (220)	$ (10)	$ (195)