Derivative instruments - Revenue from Foreign Exchange and Other Trading (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Foreign exchange revenue	$ 203	$ 222	$ 185	$ 632	$ 600
Other trading revenue	65	45	20	115	12
Gain or (loss) recognized in income on derivatives	$ (3)	$ 7	$ 1	$ 7	$ 13

Amount of gain (loss) resulting from the difference between the acquisition price and the selling price or fair value of trading assets and trading liabilities, conducted separately from customer trading activities. Includes, but is not limited to, changes in fair value of trading assets and trading liabilities.

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