Business Acquisitions and Divestitures - Pro Forma Revenue and Net Income (Details) - Stratos Wealth Holdings - USD ($) $ in Thousands |
9 Months Ended | |
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Sep. 30, 2026 |
Sep. 30, 2025 |
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| Business Combination [Line Items] | ||
| Revenues | $ 1,925,843 | $ 1,725,408 |
| Net income attributable to SEI Investments Company | $ 571,460 | $ 450,173 |
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- Definition Amount of pro forma revenue of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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