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Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2024
Significant Accounting Policies [Abstract] |
Schedule Of Securities Segregated For Regulatory Purposes |
|  | December 31,
|  | 2024 |  | 2023
|  | (in millions)
U.S. and foreign government securities |  | $ | 6,460 |  | $ | 5,684
Municipal securities |  |  | 33 |  |  | 70
Securities purchased under agreements to resell 1 |  |  | 21,353 |  |  | 29,632
|  | $ | 27,846 |  | $ | 35,386
___________________________ (1)These balances are collateralized by U.S. government securities.
Composition Of Investment |
|  | December 31,
|  | 2024 |  | 2023
|  | (in millions)
Equity method investments 1 |  | $ | 172 |  | $ | 142
Investments in equity securities at adjusted cost 2 |  |  | 29 |  |  | 22
Investments in equity securities at fair value 2 |  |  | 32 |  |  | 44
Investments in exchange memberships and equity securities of certain exchanges 2 |  |  | 2 |  |  | 2
|  | $ | 235 |  | $ | 210
______________________ (1)The Company’s share of income or losses is included in “Other income” in the consolidated statements of comprehensive income. (2)These investments do not qualify for the equity method of accounting. Dividends received are included in “Other income” in the consolidated statements of comprehensive income.
Summary Of Early Adoption On Safeguard Crypto Assets |
|  | December 31, 2023 1
|  | As Reported |  | Adjustment |  | As Adjusted
|  | (in millions)
Assets |  |  |  |  |  |  |  |  |
Other assets |  | $ | 1,127 |  | $ | (172) |  | $ | 955
Total assets |  | $ | 128,423 |  | $ | (172) |  | $ | 128,251
Liabilities |  |  |  |  |  |  |  |  |
Accounts payable, accrued expenses and other liabilities |  | $ | 676 |  | $ | (172) |  | $ | 504
Total payables |  | $ | 102,799 |  | $ | (172) |  | $ | 102,627
Total liabilities |  | $ | 114,356 |  | $ | (172) |  | $ | 114,184
Total liabilities and equity |  | $ | 128,423 |  | $ | (172) |  | $ | 128,251
______________________ (1)For the consolidated statements of cash flow, the Company considered the change in the crypto-asset safeguarding asset and the crypto-asset safeguarding liability to be non-cash items and were not included in the change in “Other assets” and “Other payables” lines in the consolidated statements of cash flows. As a result, there is no impact to periods prior to the year ended December 31, 2023.

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- Definition Tabular disclosure of information about activity for crypto asset. Excludes information about crypto asset held for platform user. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 350 -SubTopic 60 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476168/350-60-50-3 + Details
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- Definition Tabular disclosure of equity method investments including, but not limited to, name of each investee or group of investments, percentage ownership, difference between recorded amount of an investment and the value of the underlying equity in the net assets, and summarized financial information. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481687/323-10-50-3 + Details
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