Noninterest Revenue and Noninterest Expense - Principal Transactions (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Principal transactions revenue
Total trading revenue	$ 6,397	$ 3,002
Private equity gains/(losses)	103	(65)
Principal transactions	6,500	2,937
Interest rate
Principal transactions revenue
Total trading revenue	923	452
Credit
Principal transactions revenue
Total trading revenue	1,270	(702)
Foreign exchange
Principal transactions revenue
Total trading revenue	998	1,467
Equity
Principal transactions revenue
Total trading revenue	2,657	1,348
Commodity
Principal transactions revenue
Total trading revenue	$ 549	$ 437

Amount of realized and unrealized gain (loss), from the firm's direct investment activity, conducted separately from customer trading activities, and includes, but is not limited to, investments in private equity, alternative investment products, real estate, and exchanges and memberships.

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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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