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Financial Assets And Financial Liabilities (Narrative) (Details) - USD ($) | 9 Months Ended |
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Sep. 30, 2025 | Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Transfers in and/or out of Level 3 |  | $ 0 |  |
Securities Purchased Under Agreement To Resell [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Securities purchased under agreemet to resell | [1] | 30,058,000,000 |  | $ 21,353,000,000
Securities Borrowed [Member] |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Securities purchased under agreemet to resell |  | $ 2,451,000,000 | [1] | $ 0
[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.

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- Definition Amount of securities segregated for regulatory purposes, before effects of master netting arrangement, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Includes assets not subject to a master netting arrangement. + References No definition available. + Details
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