Business Acquisitions and Divestitures - Pro Forma Revenue and Net Income (Details) - Stratos Wealth Holdings - USD ($) $ in Thousands |
3 Months Ended | |
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Mar. 31, 2026 |
Mar. 31, 2025 |
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| Business Combination [Line Items] | ||
| Revenues | $ 622,183 | $ 563,328 |
| Net income attributable to SEI Investments Company | $ 174,673 | $ 151,836 |
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- Definition Amount, after tax, of pro forma income (loss) 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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- 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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