Cash, Cash Equivalents, and Cash Restricted for Regulatory Purposes for Periods Presented in Consolidated Statement of Financial Condition - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Statement of Cash Flows [Abstract]
Cash and cash equivalents	$ 1,629,363	$ 2,253,789
Cash segregated for regulatory purposes	32,441	29,018
Total cash, cash equivalents, and cash segregated for regulatory purposes	$ 1,661,804	$ 2,282,807

Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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