Investments - Summary of Carrying Value of Total Investments (Detail) (Parenthetical) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Schedule of Investments [Line Items] | ||||||
| Trading securities | [1] | $ 3,304 | $ 2,789 | |||
| Equity securities at FVTNI | [1] | 2,612 | 2,282 | |||
| Investments | [2] | 14,574 | 13,271 | |||
| Deferred Cash Compensation Plan Mutual Fund Investments [Member] | ||||||
| Schedule of Investments [Line Items] | ||||||
| Debt securities | 26 | |||||
| Investments | 29 | 37 | ||||
| Consolidated Sponsored Investment Products [Member] | ||||||
| Schedule of Investments [Line Items] | ||||||
| Trading securities | 3,271 | 2,782 | ||||
| Equity securities at FVTNI | 2,147 | 1,681 | ||||
| Investments | $ 10,402 | $ 9,131 | ||||
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- Definition Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all investments. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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 investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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