Derivative Financial Instruments - Impact of Derivatives on Consolidated Statement of Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Cash settled deferred incentive compensation awards, accelerated expense	$ 147
Derivatives not designated as hedging instruments
Derivative [Line Items]
Amount of gain (loss) on derivative recognized in income	550	$ 799	$ 269
Derivatives not designated as hedging instruments | Foreign exchange contracts | Foreign exchange trading services
Derivative [Line Items]
Amount of gain (loss) on derivative recognized in income	811	922	630
Derivatives not designated as hedging instruments | Foreign exchange contracts | Interest expense
Derivative [Line Items]
Amount of gain (loss) on derivative recognized in income	68	63	(153)
Derivatives not designated as hedging instruments | Interest rate contracts | Foreign exchange trading services
Derivative [Line Items]
Amount of gain (loss) on derivative recognized in income	3	3	(3)
Derivatives not designated as hedging instruments | Other derivative contracts | Compensation and employee benefits
Derivative [Line Items]
Amount of gain (loss) on derivative recognized in income	$ (332)	$ (189)	$ (205)