Financial Assets And Financial Liabilities (Financial Assets and Liabilities Not Measured at Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash and cash equivalents	$ 2,395	$ 4,292	$ 2,882
Cash segregated for regulatory purposes	22,888	15,903	$ 9,400
Securities - segregated for regulatory purposes	15,121	27,821
Securities borrowed	3,912	4,956
Securities purchased under agreements to resell	4,380	792
Receivables from customers	54,935	39,333
Receivables from brokers, dealers and clearing organizations	3,771	1,254
Interest Receivable	127	104
Other assets	911	594
Short-term borrowings	27	118
Securities loaned	11,769	9,838
Payable to customers	85,634	75,882
Brokers, dealers and clearing organizations	557	182
Interest Payable	8	6
at Fair Value
Cash and cash equivalents	2,395	4,292
Cash segregated for regulatory purposes	22,888	15,903
Securities - segregated for regulatory purposes	10,392	23,071
Securities borrowed	3,912	4,956
Securities purchased under agreements to resell	4,380	792
Receivables from customers	54,935	39,333
Receivables from brokers, dealers and clearing organizations	3,771	1,254
Interest Receivable	127	104
Other assets	20	13
Total financial assets, not measured at fair value	102,820	89,718
Short-term borrowings	27	118
Securities loaned	11,769	9,838
Payable to customers	85,634	75,882
Brokers, dealers and clearing organizations	557	182
Interest Payable	8	6
Total financial liabilities, not measured at fair value	97,995	86,026
Carrying Value
Cash and cash equivalents	2,395	4,292
Cash segregated for regulatory purposes	22,888	15,903
Securities - segregated for regulatory purposes	10,392	23,071
Securities borrowed	3,912	4,956
Securities purchased under agreements to resell	4,380	792
Receivables from customers	54,935	39,333
Receivables from brokers, dealers and clearing organizations	3,771	1,254
Interest Receivable	127	104
Other assets	20	13
Total financial assets, not measured at fair value	102,820	89,718
Short-term borrowings	27	118
Securities loaned	11,769	9,838
Payable to customers	85,634	75,882
Brokers, dealers and clearing organizations	557	182
Interest Payable	8	6
Total financial liabilities, not measured at fair value	97,995	86,026
Level 1 [Member]
Cash and cash equivalents	2,395	4,292
Cash segregated for regulatory purposes	22,888	15,903
Total financial assets, not measured at fair value	25,283	20,195
Short-term borrowings
Securities loaned
Payable to customers
Brokers, dealers and clearing organizations
Interest Payable
Total financial liabilities, not measured at fair value
Level 2 [Member]
Securities - segregated for regulatory purposes	10,392	23,071
Securities borrowed	3,912	4,956
Securities purchased under agreements to resell	4,380	792
Receivables from customers	54,935	39,333
Receivables from brokers, dealers and clearing organizations	3,771	1,254
Interest Receivable	127	104
Other assets	2	2
Total financial assets, not measured at fair value	77,519	69,512
Short-term borrowings	27	118
Securities loaned	11,769	9,838
Payable to customers	85,634	75,882
Brokers, dealers and clearing organizations	557	182
Interest Payable	8	6
Total financial liabilities, not measured at fair value	97,995	86,026
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	18	11
Total financial assets, not measured at fair value	18	11
Short-term borrowings
Securities loaned
Payable to customers
Brokers, dealers and clearing organizations
Interest Payable
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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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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