Segment, Geographic and Revenue Information - Institutional Securities - Investment Banking Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue from External Customer [Line Items]
Investment banking	$ 1,150	$ 2,560	$ 2,908	$ 5,400
Firm Investment banking revenues from contracts with customers (as a percent)	88.00%	90.00%	89.00%	91.00%
Institutional Securities | Operating Segments
Revenue from External Customer [Line Items]
Investment banking	$ 1,072	$ 2,376	$ 2,706	$ 4,989
Institutional Securities | Operating Segments | Institutional Securities Advisory
Revenue from External Customer [Line Items]
Investment banking	598	664	1,542	1,144
Institutional Securities | Operating Segments | Institutional Securities Underwriting
Revenue from External Customer [Line Items]
Investment banking	$ 474	$ 1,712	$ 1,164	$ 3,845