Derivatives and Hedging Activities - Derivatives Summary (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Derivatives, Fair Value [Line Items]
Derivative, gross, assets	$ 328	$ 1,006
Derivatives, gross, liabilities	992	131
Derivative asset and derivative liability netting, assets	(151)	(91)
Derivative asset and derivative liability netting, liabilities	(151)	(91)
Cash collateral netting, assets	0	(18)
Cash collateral netting, liabilities	(14)	(23)
Total derivatives assets, net	177	897
Total derivatives liabilities, net	827	17
Other Assets | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, gross, assets	48	340
Other Assets | Interest Rate Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, gross, assets	0	0
Other Assets | Foreign Exchange Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, gross, assets	48	340
Other Assets | Foreign Exchange Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, gross, assets	279	666
Other Liabilities | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivatives, gross, liabilities	772	41
Other Liabilities | Interest Rate Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivatives, gross, liabilities	8	23
Other Liabilities | Foreign Exchange Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivatives, gross, liabilities	764	18
Other Liabilities | Foreign Exchange Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivatives, gross, liabilities	$ 220	$ 90