Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Statement of Comprehensive Income [Abstract] | ||||
| Net income | $ 199,540 | $ 227,083 | $ 376,327 | $ 378,600 |
| Other comprehensive (loss) income, net of tax: | ||||
| Foreign currency translation adjustments | 293 | 16,527 | (3,494) | 21,893 |
| Unrealized (loss) gain on investments: | ||||
| Unrealized (losses) gains during the period, net of income taxes of $87, $(208), $279 and $(1,134) | (274) | 706 | (933) | 3,807 |
| Reclassification adjustment for gains realized in net income, net of income taxes of $55, $22, $202 and $31 | (205) | (76) | (684) | (108) |
| Total other comprehensive (loss) income, net of tax | (186) | 17,157 | (5,111) | 25,592 |
| Comprehensive income | 199,354 | 244,240 | 371,216 | 404,192 |
| Less: Comprehensive income attributable to the non-controlling interests | 3,882 | 0 | 6,182 | 0 |
| Comprehensive income attributable to SEI Investments Company | $ 195,472 | $ 244,240 | $ 365,034 | $ 404,192 |
| X | ||||||||||
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount, after tax and before adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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