Noninterest Income - Foreign Exchange Fees (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 1,314	$ 1,057	$ 880
Revenue not from contracts with customer	1,424	783	341
Foreign exchange fees	262	179	159
Spot contract commissions
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	240	158	146
Forward contract commissions
Disaggregation of Revenue [Line Items]
Revenue not from contracts with customer	20	20	13
Option premium fees
Disaggregation of Revenue [Line Items]
Revenue not from contracts with customer	$ 2	$ 1	$ 0