Financial Assets And Financial Liabilities (Financial Assets and Liabilities Not Measured at Fair Value) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Cash and cash equivalents	$ 3,184	$ 2,395	$ 2,838
Cash segregated for regulatory purposes	25,432	22,888	$ 23,125
Securities - segregated for regulatory purposes	31,301	15,121
Securities borrowed	3,908	3,912
Securities purchased under agreements to resell	4,860	4,380
Receivables from customers	40,424	54,935
Receivables from brokers, dealers and clearing organizations	3,321	3,771
Interest Receivable	224	127
Other assets	936	911
Short-term borrowings	35	27
Securities loaned	9,490	11,769
Customers	92,594	85,634
Brokers, dealers and clearing organizations	380	557
Interest	99	8
at Fair Value
Cash and cash equivalents	3,184	2,395
Cash segregated for regulatory purposes	25,432	22,888
Securities - segregated for regulatory purposes	25,981	10,392
Securities borrowed	3,908	3,912
Securities purchased under agreements to resell	4,860	4,380
Receivables from customers	40,424	54,935
Receivables from brokers, dealers and clearing organizations	3,321	3,771
Interest Receivable	224	127
Other assets	18	20
Total financial assets, not measured at fair value	107,352	102,820
Short-term borrowings	35	27
Securities loaned	9,490	11,769
Customers	92,594	85,634
Brokers, dealers and clearing organizations	380	557
Interest	99	8
Total financial liabilities, not measured at fair value	102,598	97,995
Carrying Value
Cash and cash equivalents	3,184	2,395
Cash segregated for regulatory purposes	25,432	22,888
Securities - segregated for regulatory purposes	25,981	10,392
Securities borrowed	3,908	3,912
Securities purchased under agreements to resell	4,860	4,380
Receivables from customers	40,424	54,935
Receivables from brokers, dealers and clearing organizations	3,321	3,771
Interest Receivable	224	127
Other assets	17	20
Total financial assets, not measured at fair value	107,351	102,820
Short-term borrowings	35	27
Securities loaned	9,490	11,769
Customers	92,594	85,634
Brokers, dealers and clearing organizations	380	557
Interest	99	8
Total financial liabilities, not measured at fair value	102,598	97,995
Level 1 [Member]
Cash and cash equivalents	3,184	2,395
Cash segregated for regulatory purposes	25,432	22,888
Total financial assets, not measured at fair value	28,616	25,283
Short-term borrowings
Securities loaned
Customers
Brokers, dealers and clearing organizations
Interest
Total financial liabilities, not measured at fair value
Level 2 [Member]
Securities - segregated for regulatory purposes	25,981	10,392
Securities borrowed	3,908	3,912
Securities purchased under agreements to resell	4,860	4,380
Receivables from customers	40,424	54,935
Receivables from brokers, dealers and clearing organizations	3,321	3,771
Interest Receivable	224	127
Other assets	2	2
Total financial assets, not measured at fair value	78,720	77,519
Short-term borrowings	35	27
Securities loaned	9,490	11,769
Customers	92,594	85,634
Brokers, dealers and clearing organizations	380	557
Interest	99	8
Total financial liabilities, not measured at fair value	102,598	97,995
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
Receivables from brokers, dealers and clearing organizations
Interest Receivable
Other assets	16	18
Total financial assets, not measured at fair value	16	18
Short-term borrowings
Securities loaned
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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Cash deposited in a special reserve account for the exclusive benefit of customers pursuant to SEC Regulations.

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