Derivatives - Derivatives Associated with Fixed Income Trading Activities (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Customer interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional	$ 4,264	$ 4,096
Assets	24	8
Liabilities	122	190
Offsetting upstream interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional	4,442	4,265
Assets	84	134
Liabilities	24	9
Forwards and futures purchased
Derivative Instruments, Gain (Loss) [Line Items]
Notional	1,660	1,421
Assets	10	1
Liabilities	0	6
Forwards and futures sold
Derivative Instruments, Gain (Loss) [Line Items]
Notional	1,753	1,426
Assets	0	7
Liabilities	$ 11	$ 0