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Significant Accounting Policies (Schedule Of Securities Segregated For Regulatory Purposes) (Details) - USD ($) $ in Millions		Sep. 30, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Securities - segregated for regulatory purposes		$ 31,335	$ 31,781
US Government Securities [Member]
Marketable Securities [Line Items]
Securities - segregated for regulatory purposes		5,687	4,641
Municipal Securities [Member]
Marketable Securities [Line Items]
Securities - segregated for regulatory purposes		39	82
Securities Purchased Under Agreement To Resell [Member]
Marketable Securities [Line Items]
Securities - segregated for regulatory purposes	[1]	$ 25,609	$ 27,058
[1] These balances are collateralized by U.S. government securities.

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- Definition

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

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