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Financial Assets And Financial Liabilities (Netting of Financial Assets) (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Offsetting Securities Borrowed [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized | [1] | $ 11,568 |  | $ 5,369
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 11,568 |  | 5,369
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  | (11,325) |  | (5,159)
Net Amount |  | 243 |  | 210
Offsetting Securities Purchased under Agreements to Resell [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized | [1] | 8,524 |  | 6,575
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 8,524 |  | 6,575
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  | (8,524) |  | (6,575)
Net Amount |  |  |  |
Total [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized | [1] | 52,680 |  | 33,381
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 52,680 |  | 33,381
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  | (52,347) |  | (33,156)
Net Amount |  | 333 |  | 225
Options [Member] |  |  |  |
Offsetting Financial Instruments Owned, At Fair Value [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized | [1] | 72 |  | 84
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 72 |  | 84
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  | (56) |  | (69)
Net Amount |  | 16 |  | 15
Currency Forward Contracts [Member] |  |  |  |
Offsetting Financial Instruments Owned, At Fair Value [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized | [1] | 7 |  |
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 7 |  |
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  |  |  |
Net Amount |  | 7 |  |
Securities Purchased Under Agreement To Resell [Member] |  |  |  |
Securities, Segregated For Regulatory Purposes, Purchased Under Agreements To Resell [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized | [1] | 30,058 |  | 21,353
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 30,058 |  | 21,353
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  | (30,058) |  | (21,353)
Net Amount |  |  |  |
Securities Borrowed [Member] |  |  |  |
Securities, Segregated For Regulatory Purposes, Purchased Under Agreements To Resell [Abstract] |  |  |  |
Gross Amounts of Financial Assets Recognized |  | 2,451 | [1] | $ 0
Amounts Offset in the Condensed Consolidated Statement of Financial Condition | [2] |  |  |
Net Amounts Presented in the Condensed Consolidated Statement of Financial Condition |  | 2,451 |  |
Amounts Not Offset in the Condensed Consolidated Statement of Financial Condition: Cash or Financial Instruments |  | (2,384) |  |
Net Amount |  | $ 67 |  |
[1] | As of September 30, 2025 and December 31, 2024, the Company had $30.1 billion and $21.4 billion, respectively, of securities purchased under agreements to resell, and $2.5 billion and $0, respectively, of securities borrowed that were segregated to satisfy regulatory requirements. These securities are included in “Securities - segregated for regulatory purposes” in the condensed consolidated statements of financial condition.
[2] | The Company did not have any balances eligible for netting in accordance with ASC Topic 210-20 as of September 30, 2025 and December 31, 2024.

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