Investments and Other Marketable Securities - Narrative (Details) - USD ($) $ in Thousands |
9 Months Ended | ||
|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
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| Schedule of Investments [Line Items] | |||
| Investment products and equities | $ 70,144 | $ 67,414 | |
| Securities owned | 25,750 | 33,777 | |
| Cash equivalents at fair value | 255,318 | 235,933 | |
| SEI-Sponsored Open-Ended Money Market Mutual Funds | |||
| Schedule of Investments [Line Items] | |||
| Cash and cash equivalents | 89,189 | 201,675 | |
| Investment Funds Sponsored by LSV | |||
| Schedule of Investments [Line Items] | |||
| Investments in limited partnership funds | 14,176 | $ 11,593 | |
| Unrealized gains (losses) on investments | $ 2,583 | $ 2,393 | |
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- Definition Investment Products And Equities No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of long-term investments classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unrealized gain (loss) on investment. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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