Financial Assets And Financial Liabilities (Financial Assets and Liabilities Not Measured at Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Cash and cash equivalents	$ 3,214	$ 3,436	$ 2,667
Cash segregated for regulatory purposes	24,354	25,167	$ 24,581
Securities - segregated for regulatory purposes	36,987	31,781
Securities borrowed	5,306	4,749
Securities purchased under agreements to resell	6,699	6,029
Receivables from customers	39,491	38,760
Brokers, dealers and clearing organizations	1,666	3,469
Interest Receivable	384	341
Other assets	985	926
Short-term borrowings	10	18
Securities loaned	10,719	8,940
Customers	94,897	93,195
Brokers, dealers and clearing organizations	369	291
Interest	237	193
at Fair Value
Cash and cash equivalents	3,214	3,436
Cash segregated for regulatory purposes	24,354	25,167
Securities - segregated for regulatory purposes	30,559	27,058
Securities borrowed	5,306	4,749
Securities purchased under agreements to resell	6,699	6,029
Receivables from customers	39,491	38,760
Brokers, dealers and clearing organizations	1,666	3,469
Interest Receivable	384	341
Other assets	18	18
Total financial assets, not measured at fair value	111,691	109,027
Short-term borrowings	10	18
Securities loaned	10,719	8,940
Customers	94,897	93,195
Brokers, dealers and clearing organizations	369	291
Interest	237	193
Total financial liabilities, not measured at fair value	106,232	102,637
Carrying Value
Cash and cash equivalents	3,214	3,436
Cash segregated for regulatory purposes	24,354	25,167
Securities - segregated for regulatory purposes	30,559	27,058
Securities borrowed	5,306	4,749
Securities purchased under agreements to resell	6,699	6,029
Receivables from customers	39,491	38,760
Brokers, dealers and clearing organizations	1,666	3,469
Interest Receivable	384	341
Other assets	17	17
Total financial assets, not measured at fair value	111,690	109,026
Short-term borrowings	10	18
Securities loaned	10,719	8,940
Customers	94,897	93,195
Brokers, dealers and clearing organizations	369	291
Interest	237	193
Total financial liabilities, not measured at fair value	106,232	102,637
Level 1 [Member]
Cash and cash equivalents	3,214	3,436
Cash segregated for regulatory purposes	24,354	25,167
Total financial assets, not measured at fair value	27,568	28,603
Short-term borrowings
Securities loaned
Securities sold under agreements to repurchase
Customers
Brokers, dealers and clearing organizations
Interest
Total financial liabilities, not measured at fair value
Level 2 [Member]
Securities - segregated for regulatory purposes	30,559	27,058
Securities borrowed	5,306	4,749
Securities purchased under agreements to resell	6,699	6,029
Receivables from customers	39,491	38,760
Brokers, dealers and clearing organizations	1,666	3,469
Interest Receivable	384	341
Other assets	2	2
Total financial assets, not measured at fair value	84,107	80,408
Short-term borrowings	10	18
Securities loaned	10,719	8,940
Customers	94,897	93,195
Brokers, dealers and clearing organizations	369	291
Interest	237	193
Total financial liabilities, not measured at fair value	106,232	102,637
Level 3 [Member]
Cash and cash equivalents
Cash segregated for regulatory purposes
Securities - segregated for regulatory purposes
Securities borrowed
Securities purchased under agreements to resell
Receivables from customers
Brokers, dealers and clearing organizations
Interest Receivable
Other assets	16	16
Total financial assets, not measured at fair value	16	16
Short-term borrowings
Securities loaned
Securities sold under agreements to repurchase
Customers
Brokers, dealers and clearing organizations
Interest
Total financial liabilities, not measured at fair value

Margin loans to clients stated net of allowance for doubtful accounts.

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Amount payable to other broker-dealer and clearing organization, including, but not limited to, security failed-to-receive, deposit received for security loaned, open transaction, and floor-brokerage payable.

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Amount payable to customer by broker-dealer.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Cash deposited in a special reserve account for the exclusive benefit of customers pursuant to SEC Regulations.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount of assets classified as other.

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Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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