Derivative Financial Instruments - Schedule of the Fair Values of Derivative Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	$ 15,764	$ 19,707
Fair value of derivative liabilities	16,242	19,602
Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	15,754	19,694
Fair value of derivative liabilities	16,073	19,416
Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	10	13
Fair value of derivative liabilities		4
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	15,698	19,498
Fair value of derivative liabilities	16,219	19,335
Derivatives not designated as hedging instruments | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	15,698	19,498
Fair value of derivative liabilities	16,050	19,153
Derivatives not designated as hedging instruments | Other derivative contracts
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	0	0
Fair value of derivative liabilities	169	182
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	66	209
Fair value of derivative liabilities	23	267
Derivatives designated as hedging instruments | Foreign exchange contracts
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	56	196
Fair value of derivative liabilities	23	263
Derivatives designated as hedging instruments | Interest rate contracts
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	10	13
Fair value of derivative liabilities	$ 0	$ 4