Financial Assets And Financial Liabilities (Financial Assets and Liabilities Not Measured at Fair Value) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021
Cash and cash equivalents	$ 2,881	$ 2,395	$ 3,218
Cash segregated for regulatory purposes	23,536	22,888	$ 22,099
Securities - segregated for regulatory purposes	30,709	15,121
Securities borrowed	3,855	3,912
Securities purchased under agreements to resell	6,288	4,380
Receivables from customers	42,552	54,935
Receivables from brokers, dealers and clearing organizations	1,939	3,771
Interest Receivable	150	127
Other assets	925	911
Short-term borrowings	17	27
Securities loaned	10,696	11,769
Customers	90,765	85,634
Brokers, dealers and clearing organizations	308	557
Interest	36	8
at Fair Value
Cash and cash equivalents	2,881	2,395
Cash segregated for regulatory purposes	23,536	22,888
Securities - segregated for regulatory purposes	23,346	10,392
Securities borrowed	3,855	3,912
Securities purchased under agreements to resell	6,288	4,380
Receivables from customers	42,552	54,935
Receivables from brokers, dealers and clearing organizations	1,939	3,771
Interest Receivable	150	127
Other assets	19	20
Total financial assets, not measured at fair value	104,566	102,820
Short-term borrowings	17	27
Securities loaned	10,696	11,769
Customers	90,765	85,634
Brokers, dealers and clearing organizations	308	557
Interest	36	8
Total financial liabilities, not measured at fair value	101,822	97,995
Carrying Value
Cash and cash equivalents	2,881	2,395
Cash segregated for regulatory purposes	23,536	22,888
Securities - segregated for regulatory purposes	23,346	10,392
Securities borrowed	3,855	3,912
Securities purchased under agreements to resell	6,288	4,380
Receivables from customers	42,552	54,935
Receivables from brokers, dealers and clearing organizations	1,939	3,771
Interest Receivable	150	127
Other assets	18	20
Total financial assets, not measured at fair value	104,565	102,820
Short-term borrowings	17	27
Securities loaned	10,696	11,769
Customers	90,765	85,634
Brokers, dealers and clearing organizations	308	557
Interest	36	8
Total financial liabilities, not measured at fair value	101,822	97,995
Level 1 [Member]
Cash and cash equivalents	2,881	2,395
Cash segregated for regulatory purposes	23,536	22,888
Total financial assets, not measured at fair value	26,417	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	23,346	10,392
Securities borrowed	3,855	3,912
Securities purchased under agreements to resell	6,288	4,380
Receivables from customers	42,552	54,935
Receivables from brokers, dealers and clearing organizations	1,939	3,771
Interest Receivable	150	127
Other assets	2	2
Total financial assets, not measured at fair value	78,132	77,519
Short-term borrowings	17	27
Securities loaned	10,696	11,769
Customers	90,765	85,634
Brokers, dealers and clearing organizations	308	557
Interest	36	8
Total financial liabilities, not measured at fair value	101,822	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	17	18
Total financial assets, not measured at fair value	17	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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