Significant Accounting Policies (Schedule Of Securities Segregated For Regulatory Purposes) (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
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|---|---|---|---|---|
| Marketable Securities [Line Items] | ||||
| Securities - segregated for regulatory purposes | $ 41,889 | $ 26,521 | ||
| US And Foreign Government Securities [Member] | ||||
| Marketable Securities [Line Items] | ||||
| Securities - segregated for regulatory purposes | 7,438 | 6,031 | ||
| Municipal Securities [Member] | ||||
| Marketable Securities [Line Items] | ||||
| Securities - segregated for regulatory purposes | 65 | 66 | ||
| Securities Purchased Under Agreement To Resell [Member] | ||||
| Marketable Securities [Line Items] | ||||
| Securities - segregated for regulatory purposes | [1] | 32,117 | 17,981 | |
| Securities Borrowed [Member] | ||||
| Marketable Securities [Line Items] | ||||
| Securities - segregated for regulatory purposes | [1] | $ 2,269 | $ 2,443 | |
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