Financial Assets And Financial Liabilities (Financial Assets and Liabilities Not Measured at Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Cash and cash equivalents	$ 2,667	$ 2,395	$ 2,627
Cash segregated for regulatory purposes	24,581	22,888	$ 21,204
Securities - segregated for regulatory purposes	24,350	15,121
Securities borrowed	4,445	3,912
Securities purchased under agreements to resell	6,268	4,380
Receivables from customers	48,306	54,935
Receivables from brokers, dealers and clearing organizations	2,188	3,771
Interest Receivable	118	127
Other assets	923	911
Short-term borrowings	11	27
Securities loaned	11,379	11,769
Securities sold under agreements to repurchase	300
Customers	91,097	85,634
Brokers, dealers and clearing organizations	230	557
Interest	8	8
at Fair Value
Cash and cash equivalents	2,667	2,395
Cash segregated for regulatory purposes	24,581	22,888
Securities - segregated for regulatory purposes	16,934	10,392
Securities borrowed	4,445	3,912
Securities purchased under agreements to resell	6,268	4,380
Receivables from customers	48,306	54,935
Receivables from brokers, dealers and clearing organizations	2,188	3,771
Interest Receivable	118	127
Other assets	19	20
Total financial assets, not measured at fair value	105,526	102,820
Short-term borrowings	11	27
Securities loaned	11,379	11,769
Securities sold under agreements to repurchase	300
Customers	91,097	85,634
Brokers, dealers and clearing organizations	230	557
Interest	8	8
Total financial liabilities, not measured at fair value	103,025	97,995
Carrying Value
Cash and cash equivalents	2,667	2,395
Cash segregated for regulatory purposes	24,581	22,888
Securities - segregated for regulatory purposes	16,934	10,392
Securities borrowed	4,445	3,912
Securities purchased under agreements to resell	6,268	4,380
Receivables from customers	48,306	54,935
Receivables from brokers, dealers and clearing organizations	2,188	3,771
Interest Receivable	118	127
Other assets	18	20
Total financial assets, not measured at fair value	105,525	102,820
Short-term borrowings	11	27
Securities loaned	11,379	11,769
Securities sold under agreements to repurchase	300
Customers	91,097	85,634
Brokers, dealers and clearing organizations	230	557
Interest	8	8
Total financial liabilities, not measured at fair value	103,025	97,995
Level 1 [Member]
Cash and cash equivalents	2,667	2,395
Cash segregated for regulatory purposes	24,581	22,888
Total financial assets, not measured at fair value	27,248	25,283
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	16,934	10,392
Securities borrowed	4,445	3,912
Securities purchased under agreements to resell	6,268	4,380
Receivables from customers	48,306	54,935
Receivables from brokers, dealers and clearing organizations	2,188	3,771
Interest Receivable	118	127
Other assets	2	2
Total financial assets, not measured at fair value	78,261	77,519
Short-term borrowings	11	27
Securities loaned	11,379	11,769
Securities sold under agreements to repurchase	300
Customers	91,097	85,634
Brokers, dealers and clearing organizations	230	557
Interest	8	8
Total financial liabilities, not measured at fair value	103,025	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
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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