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Fair Value - Schedule of Equity Method Investments Key Assumptions (Details) $ in Millions | Sep. 30, 2025 USD ($) | Mar. 31, 2025 USD ($)
--- | --- | ---
Schedule of Equity Method Investments [Line Items] |  |
Equity investments | $ 294 | $ 300
Level 3 |  |
Schedule of Equity Method Investments [Line Items] |  |
Equity investments | $ 200 | $ 200
Level 3 | Valuation Technique, Probability-Weighted, Expected Return |  |
Schedule of Equity Method Investments [Line Items] |  |
Equity method investments, fair value option, time to future exit | 9 months 18 days | 9 months 18 days
Level 3 | Valuation Technique, Probability-Weighted, Expected Return | Measurement Input, Probability Of IPO, Time To Future Exit Scenario |  |
Schedule of Equity Method Investments [Line Items] |  |
Equity method investments, fair value option, measurement input | 1 | 1
Level 3 | Minimum | Valuation Technique, Discounted Cash Flow | LTM Revenue Multiple |  |
Schedule of Equity Method Investments [Line Items] |  |
Equity method investments, fair value option, measurement input | 1.1 | 1.1
Level 3 | Maximum | Valuation Technique, Discounted Cash Flow | LTM Revenue Multiple |  |
Schedule of Equity Method Investments [Line Items] |  |
Equity method investments, fair value option, measurement input | 1.3 | 1.3

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