Noninterest Revenue and Noninterest Expense - Investment Banking Fees (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Schedule of Noninterest revenue [Line Items]
Underwriting	$ 1,357	$ 905
Advisory	597	744
Total investment banking fees	1,954	1,649
Equity
Schedule of Noninterest revenue [Line Items]
Underwriting	354	233
Debt
Schedule of Noninterest revenue [Line Items]
Underwriting	$ 1,003	$ 672

Includes (1) underwriting revenue (the spread between the resale price received and the cost of the securities and related expenses) generated through the purchasing, distributing and reselling of new issues of securities (alternatively, could be a secondary offering of a large block of previously issued securities); and (2) fees earned for mergers, acquisitions, divestitures, restructurings, and other types of financial advisory services.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(b),(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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Balance Type:	credit
Period Type:	duration