Financial Instruments Subject to Off-Balance Sheet Credit Risk (Summary of the Fair Value of Client Securities Available to Utilize as Collateral and Amounts Pledged) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Securities Financing Transaction [Line Items]
Fair value of client securities available to be pledged	$ 86,977	$ 86,775
Total collateral pledged to third parties	27,194	19,939
Fulfillment of Requirements with the Options Clearing Corporation [Member]
Securities Financing Transaction [Line Items]
Total collateral pledged to third parties	15,847	11,717
Fulfillment of Client Short Sales [Member]
Securities Financing Transaction [Line Items]
Total collateral pledged to third parties	7,447	4,750
Securities Lending to Other Broker-Dealers [Member]
Securities Financing Transaction [Line Items]
Total collateral pledged to third parties	3,900	3,472
Fully Paid Client Securities [Member]
Securities Financing Transaction [Line Items]
Total collateral pledged to third parties	$ 195	$ 160